Prince ' s Palace of Monaco The Prince ' s Palace of Monaco is the official residence of the Prince of Monaco . Built in 1191 as a Genoese fortress , during its long and often dramatic history it has been bombarded and besieged by many foreign powers . Since the end of the 13th century , it has been the stronghold and home of the Grimaldi family who first captured it in 1297 . The Grimaldi ruled the area first as feudal lords , and from the 17th century as sovereign princes , but their power was often derived from fragile agreements with their larger and stronger neighbours . Thus while other European sovereigns were building luxurious , modern Renaissance and Baroque palaces , politics and common sense demanded that the palace of the Monegasque rulers be fortified . This unique requirement , at such a late stage in history , has made the palace at Monaco one of the most unusual in Europe . Ironically , when its fortifications were finally relaxed during the late 18th century , it was seized by the French and stripped of its treasures , and fell into decline , while the Grimaldi were exiled for over 20 years . The Grimaldi ' s occupation of their palace is also unusual because , unlike other European ruling families , the absence of alternative palaces and land shortages have resulted in their use of the same residence for more than seven centuries . Thus , their fortunes and politics are directly reflected in the evolution of the palace . Whereas the Romanovs , Bourbons , and Habsburgs could , and frequently did , build completely new palaces , the most the Grimaldi could achieve when enjoying good fortune , or desirous of change , was to build a new tower or wing , or , as they did more frequently , rebuild an existing part of the palace . Thus , the Prince ' s Palace reflects the history not only of Monaco , but of the family which in 1997 celebrated 700 years of rule from the same palace . During the 19th and early 20th centuries , the palace and its owners became symbols of the slightly risqué glamour and decadence that were associated with Monte Carlo and the French Riviera . Glamour and theatricality became reality when the American film star Grace Kelly became chatelaine to the palace in 1956 . In the 21st century , the palace remains the residence of the current Prince of Monaco . Princely Palace . The palace is a blend of architectural styles ; its ancient origins are indicated by a lack of symmetry . Thus to evaluate the architecture , wings and blocks have to be observed separately . The principal façade appears as a terrace of Renaissance style palazzi from differing periods of the Renaissance era ( " Illustrations 1 and 12 " ) which — even though they form only one palace — is exactly what they are . These wings are however united by their common rusticated ground floor . This Renaissance architecture seems to mask earlier fortifications , the towers of which rise behind the differing classical façades . These towers — many complete with crenellation s and machicolation s — were actually mostly rebuilt during the 19th century . At the rear of the palace the original medieval fortifications seem untouched by time . ( " Illustration 4 " ) . A greater architectural harmony has been achieved within the court of honour around which the palace is built , where two tiers of frescoed open arcades serve as both a ceremonial balcony for the prince ' s appearances and a state entrance and corridor linking the formal state room s of the palace . The most notable of the many rooms are the state apartments . These were laid out from the 16th century onwards , and were enhanced in the style of those at Versailles during the 18th century . In the 19th century and again during the late 20th century , large scale restoration of the state rooms consolidated the 18th century style which prevails today . Designed as an enfilade and a ceremonial route to the throne room , the processional route begins with an external horseshoe - shaped staircase which leads from the court of honour to the open gallery known as the Gallery of Hercules . From here guests enter the Mirror Gallery , a long hall inspired by the Hall of Mirrors at Versailles . This gallery leads to the first of the state rooms , the Officer ' s Room , where guests are greeted by court officials before an audience with the prince in the Throne Room . From the Officer ' s Hall the enfilade continues to the Blue Room . This large drawing room , decorated with blue brocade , is hung with Grimaldi family portraits and has chandelier s of Murano glass . The following room , the largest of the state apartments , is the Throne Room . Its ceiling and frescoes were executed by Orazio de Ferrari and depict the surrender of Alexander the Great . The throne , in the Empire style , is positioned on a dais , beneath a red silk canopy of estate surmounted by a gilt crown . The floors are of Carrara marble . All state ceremonies have been held in this room since the 16th century . Other rooms in the state suite include the Red Room — so called because its walls are covered in red brocade — a large drawing room containing paintings by Jan Brueghel and Charles Le Brun . Like much of the palace the room contains ornate 18th - century French - style furniture . From the Red Room leads the York Room . Furnished as a state bedchamber , this room is frescoed with illustrations of the four seasons by Gregorio de Ferrari . The following room , known as the Yellow Room ( or sometimes as the Louis XV Bedchamber ) , is another state bedroom . The most remarkable room in the suite is the Mazarin Room . This drawing room is lined with Italian gilded and painted polychrome boiseries by craftsmen brought to France by Cardinal Mazarin , who was related by marriage to the Grimaldi . Cardinal Mazarin ' s portrait hangs above the fireplace . While the overriding atmosphere of the interior and exterior of the palace is of the 18th century , the palace itself is not . Much of its appearance is a result of a long evolution dating from the 12th century , overshadowed by heavy restoration and refurnishing during the 19th and 20th centuries . Grimaldi fortress . Monaco ' s history predates the Roman occupation of AD 122 . Its large natural harbour ensured a steady stream of visitors from Byblos , Tyre , and Sidon . Later the Phoenicians came to trade silk , oil , and spices with the natives . It was the Phoenicians who introduced to this area of the Mediterranean their god Melkart , later known by the Romans as " Hercules Monoikos " . It was after this god that the Romans renamed the area " Portus Hercules Moneici " , which has evolved to the present name of Monaco . The seat of the Prince of Monaco was established on the Rocher de Monaco ( " Illustration 5 " ) as a fortress in 1191 when the harbour , that is today lined by Monte Carlo , was acquired by the Republic of Genoa . The harbour and its immediate area were given to the Genoese by the Emperor Henry IV with the proviso that the Genoese protect the coastline from piracy . Further territory was ceded to the new owners by the Council of Peille and the Abbaye de Saint Pons . In 1215 work began on a new fortress , comprising four towers connected by rampart s protected by a curtain wall . This forms the core of the present palace . Genoa was important in the politics of 12th - century Europe . The Genoese were a nation of merchants , and such was their wealth that they frequently fulfilled a role as bankers to the other nation states . However , the Genoese became divided following the rift caused when the Emperor Frederick II challenged the power of Pope Innocent IV . Two distinct camps formed : the Guelphs who supported the pope and the Ghibellines who were loyal to the imperial crown . Siding with the Guelphs were one of the patrician families of Genoa — the Grimaldi . Throughout the 13th century these two groups fought . Finally at the end of the century the Ghibellines were victorious and banished their opponents , including the Grimaldi , from Genoa . The Grimaldi settled in the area today known as the French Riviera . Several castles in the area are still known as Chateau Grimaldi , and testify to the strong presence of various branches of the family in the vicinity . Legend relates that in January 1297 François Grimaldi , disguised as a monk , sought shelter at the castle . On obtaining entry he murdered the guard , whereupon his men appeared and captured the castle . Thus the fortress became the stronghold of the Grimaldi . This event is commemorated by a statue of François Grimaldi in the precincts of the palace ( " Illustration 6 " ) and in the arms of the House of Grimaldi where François is depicted wielding a sword while in the garb of a monk ( " Illustration 2 " ) . Charles I , who ruled from 1331 to 1357 , and was the son of François Grimaldi ' s cousin Rainier I , significantly enlarged the fortress by adding two large buildings : one against the eastern ramparts and the second looking out over the sea . This changed the appearance of the fortress , making it appear more of a fortified house than a fortress . The fortifications remained very necessary , for during the next three decades the fortress was alternately lost and regained by the Grimaldi to the Genoese . In 1341 the Grimaldi took Menton and then Roquebrune , thus consolidating their power and strength in the area . Subsequently they strengthened not only the defences of the harbour but also their fortress on the Rocher . The Grimaldi ' s stronghold was now a power base from which the family ruled a large but very vulnerable area of land . For the next hundred years the Grimaldi defended their territory from attacks by other states which included Genoa , Pisa , Venice , Naples , France , Spain , Germany , England and Provence . The fortress was frequently bombarded , damaged , and restored . Gradually the Grimaldi began to make an alliance with France which strengthened their position . Now more secure , the Grimaldi lords of Monaco now began to recognise the need not only to defend their territory , but also to have a home reflecting their power and prestige . Throughout the 15th century , both the fortress and the Rocher continued to be extended and further defended until it became a garrison accommodating some 400 troops . The slow transformation from fortified house to palace ( " Illustration 7 " ) began during this era , first with building by Lamberto Grimaldi , Lord of Monaco ( who between 1458 and 1494 was " a noteworthy ruler who handled diplomacy and the sword with equal talent " ) , and then by his son Jean II . This period saw the extension of the east side of the fortress with a three – floored wing , guarded by high scalloped walls connecting the bastion towers — St Mary ( M in " Illustration 7 " ) , Middle ( K ) and South ( H ) . This large new wing contained the palace ' s principal room , the State Hall ( today known as the Guard Room ) . Here the princes carried out their official business and held court . Further , more luxurious , rooms complete with balconies and loggia s were designed for the private use of the Grimaldi family . In 1505 Jean II was killed by his brother Lucien . Fortress to palace . Lucien I ( 1505 – 1523 ) . Jean II was succeeded by his brother Lucien I . Peace did not reign in Monaco for long ; in December 1506 14 , 000 Genoese troops besieged Monaco and its castle , and for five months 1 , 500 Monégasques and mercenaries defended the Rocher before achieving victory in March 1507 . This left Lucien I to walk a diplomatic tightrope between France and Spain in order to preserve the fragile independence of the tiny state which was in truth subject to Spain . Lucien immediately set about repairing the ravages of war to the fortified palace which had been damaged by heavy bombardment . To the main wing ( see " Illustrations 3 & 7 " – H to M ) , built by Prince Lambert and extended during the reign of Jean II , he now added a large wing ( H to C ) which today houses the state apartments . Honoré I ( 1523 – 1581 ) . During the reign of Honoré I the internal transformation from fortress to palace was continued . The Treaty of Trodesillas at the beginning of Honoré ' s rule clarified Monaco ' s position as a protectorate of Spain , and thus later of the Holy Roman Emperor Charles V . This provided the security to allow the Lord of Monaco to concentrate on the more comfortable side of his residence rather than the constant need to defend it . The courtyard was rebuilt , the architect Dominique Gallo designing two arcades , stretching between points H and C . The arcades , fronting the earlier wing by Lucien I , each have twelve arches , decorated by white marble balustrading on the upper level . Today the upper arcades are known as the " Galerie d ' Hercule " ( gallery of Hercules ) because their ceilings were painted with scenes depicting the Labours of Hercules by Orazio de Ferrari during the later reign of Honoré II . These arcades or loggia s provide corridors to the state rooms in the south wing ( today known as the State Rooms Wings ) . On the other side of the courtyard a new wing was constructed and the Genoese artist Luca Cambiasi was charged with painting its external walls with frescoes . It is thought that the galleries ( B ) to the north wing overlooking the harbour were built at this time . Further enlargements were carried out in order to entertain the Emperor Charles V in 1529 , when he stayed four nights at the palace during his journey in state to Bologna for his coronation by Pope Clement VII . Architecturally this was an exciting period , but Honoré I was unable to remodel the fortress in the grand style of a Renaissance palazzo . In spite of the Spanish protection , the risk of attack from France was high and defence remained Honoré ' s main priority . With this in mind he added two new features : All Saints Tower ( F ) and the Serravalle Bastion ( G ) . All Saints Tower was semi - circular and guarded the end of the rock promontory . Complete with gun platforms and cannon , it was connected to man - made caves in the rock itself . Subterranean passages also linked it to the Serravalle Bastion , which was in essence a three - storey gun tower bristling with cannon . Underneath the courtyard a cistern was installed , providing sufficient water for 1000 troops for a 20 - month siege , with a huge vaulted ceiling supported by nine columns . Monaco was to remain politically vulnerable for another century and little building work took place from 1581 until 1604 , during the reigns of Prince Charles II and Prince Hercule . Honoré II ( 1597 – 1662 ) . Monaco ' s vulnerability was further brought home in 1605 when the Spanish installed a garrison there . In 1633 Honoré II ( " Illustration 8 " ) , was officially addressed as " Serene Prince " by the Spanish king , thus recognizing Monaco as a principality for the first time . However , as Spanish troops were currently in occupation , this recognition was seen as little more than a gesture to keep Honoré happy . Honoré II was a francophile . Following his education in Milan , he had been cultivated by the intellectual salon s of Paris . Thus , having close affinities with France both culturally and politically , he rebelled against the Spanish presence in Monaco . While he realised that Monaco needed the protection of another power , France was Honoré II ' s favoured choice . In 1641 , heavily supported by the French , he attacked the Spanish garrison and expelled the Spanish , declaring " the glorious liberty of Monaco " . The liberty mentioned was entirely dependent on France , as Monaco now entered a period as a protectorate of France which would last until 1814 . As a result of this action Honoré II is today regarded as the hero of Monaco . Highly educated and a patron of the arts , Honoré II , secure on his throne , began collecting works by Titian , Dürer , Raphael , Rubens and Michelangelo which formed the basis of the art collection that furnished the palace slowly evolving from the Monaco fortress . Over the following 30 - year period he transformed it into a palace suitable for a prince ( " Illustration 9 " ) . He commissioned the architect Jacques Catone not only to enlarge the palace , but also to soften its grim fortified appearance . The main façade facing the square , the " front " of the palace , was given decorative embellishments . The upper loggias ( B ) to the right of the entrance were glazed . Inside the palace the State Rooms Wing was restyled and the enfilade of state apartments created . A new chapel adorned by a cupola ( built on the site marked D ) was dedicated to St John the Baptist . This new work helped conceal the forbidding Serravalle Bastion from the courtyard , to create the lighter atmosphere of a Renaissance palazzo . Absentee landlords and revolution ( 1662 – 1815 ) . During the late 17th century and early 18th century , while Monaco was officially an independent state , it was in reality a province of France . Its rulers spent much of their time at the French court , in this way resembling the absentee landlord s so prevalent at the time amongst the French aristocracy . The lure of Versailles was greater than that of their own country . Honoré II was succeeded by his grandson , Prince Louis I . The new prince had an urbane personality and spent much time with his wife at the French court , where he enjoyed the unusual distinction of being both a foreign head of state and a peer of France . Impressed by the palaces of the French king , who had employed the architect Jean du Cerceau to carry out alterations to the palace at Fontainebleau , Louis I used Fontainebleau as the inspiration for enhancements to his palace at Monaco . Thus he was responsible for two of the palace ' s most notable features : the entrance — a huge Baroque arch surmounted by a broken pediment bearing the Grimaldi Arms ( " Illustration 10 " ) — and more memorable still , a double horseshoe staircase modelled on that at Fontainebleau . The thirty steps which compose the staircase are said to have been sculpted from a single block of Carrara marble . Both the architrave of the new entrance and the horseshoe stairs were designed by Antoine Grigho , an architect from Como . A prince noted for the permissiveness of his private life , Louis I ' s prodigality was notorious . While visiting England in 1677 he incurred the ire of King Charles II by showering expensive gifts on Hortense Mancini , the king ' s mistress . The English and Prince Louis later became political enemies when Louis took part in the Anglo - Dutch Wars against England , leading his own Monaco Cavalry into battles in Flanders and Franche - Comté . These acts earned Louis the gratitude of Louis XIV who made him ambassador to the Holy See , charged with securing the Spanish Succession . However , the cost of upholding his position at the papal court caused him to sell most of his grandfather Honoré II ' s art collection , denuding the palace he had earlier so spectacularly enhanced . Louis died before securing the Spanish throne for France , an act which would have earned the Grimaldi huge rewards . Instead Europe was immediately plunged into turmoil as the War of the Spanish Succession began . In 1701 , Prince Antoine succeeded Louis I and inherited an almost bankrupt Monaco , though he did further embellish the Royal Room . On its ceiling , Gregorio de Ferrari and Alexandre Haffner depicted a figure of Fame surrounded by lunette s illustrating the four seasons . Antoine ' s marriage to Marie of Lorraine was unhappy and yielded only two daughters . Monaco ' s constitution confined the throne to members of the Grimaldi family alone , and Antoine was thus keen for his daughter Princess Louise - Hippolyte ( " Illustration 11 " ) to wed a Grimaldi cousin . However , the state of the Grimaldi fortunes , and the lack of ( the politically necessary ) approval from King Louis XIV , dictated otherwise . Louise - Hippolyte was married to Jacques de Goyon Matignon , a wealthy aristocrat from Normandy . Louise - Hippolyte succeeded her father as sovereign of Monaco in 1731 but died just months later . The King of France , confirming Monaco ' s subservient state to France , ignored the protests of other branches of the Grimaldi family , overthrew the Monégasque constitution , and approved the succession of Jacques de Goyon Matignon as Prince Jacques I . Jacques I assumed the name and arms of the Grimaldi , but the French aristocracy showed scant respect towards the new prince who had risen from their ranks and chose to spend his time absent from Monaco . He died in 1751 and was succeeded by his and Louise - Hippolyte ' s son Prince Honoré III . Honoré III married Catherine Brignole in 1757 and later divorced her . Interestingly , before his marriage Honoré III had been conducting an affair with his future mother - in - law . After her divorce Marie Brignole married Louis Joseph de Bourbon , prince de Condé , a member of the fallen French royal house , in 1798 . Ironically , the Grimaldi fortunes were restored when descendants of both Hortense Mancini and Louis I married : Louise d ' Aumont Mazarin married Honoré III ' s son and heir , the future Honoré IV . This marriage in 1776 was extremely advantageous to the Grimaldi , as Louise ' s ancestress Hortense Mancini had been the heiress of Cardinal Mazarin . Thus Monaco ' s ruling family acquired all the estates bequeathed by Cardinal Mazarin , including the Duchy of Rethel , and the Principality of Château - Porcien . Honoré III was a soldier who fought at both Fontenoy and Rocourt . He was happy to leave Monaco to be governed by others , most notably a former tutor . It was on one of Honoré III ' s rare visits to the palace in 1767 that illness forced Edward , Duke of York , to land at Monaco . The sick duke was allocated the state bedchamber where he promptly died . Since that date the room has been known as the York Room . Despite its lack of continuous occupancy , by the final quarter of the 18th century the palace was once again a " splendid place " ( " Illustration 12 " ) . However revolution was afoot , and in the late 1780s Honoré III had to make concessions to his people who had caught the revolutionary ideas from their French neighbours . This was only the beginning of the Grimaldi ' s problems . In 1793 the leaders of the French Revolution annexed Monaco . The prince was imprisoned in France and his property and estates , including the palace , were forfeited to France . The palace was looted by the prince ' s subjects , and what remained of the furnishings and art collection was auctioned by the French government . Further changes were heaped on both the country and palace . Monaco was renamed " Fort d ' Hercule " and became a canton of France while the palace became a military hospital and poorhouse . In Paris , the prince ' s daughter - in - law Francoise - Thérèse de Choiseul - Stainville ( 1766 – 1794 ) was executed , one of the last to be guillotined during the Reign of Terror . Honoré III died in 1795 in Paris , where he had spent most of his life , without regaining his throne . 19th century . Regaining the palace . Honoré III was succeeded by his son Honoré IV ( 1758 – 1819 ) whose marriage to Louise d ' Aumont Mazarin had done so much to restore the Grimaldi fortunes . Much of this fortune had been depleted by the hardships of the revolution . On 17 June 1814 under the Treaty of Paris , the Principality of Monaco was restored to Honoré IV . The fabric of the palace had been completely neglected during the years in which the Grimaldi had been exiled from Monaco . Such was the state of disrepair that part of the east wing had to be demolished along with Honoré II ' s bathing pavilion , which stood on the site occupied today by the Napoleon Museum and the building housing the palace archives . Restoration . Honoré IV died shortly after his throne was restored to him , and structural restoration of the palace began under Honoré V and was continued after his death in 1841 by his brother Prince Florestan . However , by the time of Florestan ' s accession , Monaco was once again experiencing political tensions caused by financial problems . These resulted from its position as a protectorate of Sardinia , the country to which it had been ceded by France following the end of the Napoleonic wars . Florestan , an eccentric ( he had been a professional actor ) , left the running of Monaco to his wife , Maria Caroline Gibert de Lametz . Despite her attempts to rule , her husband ' s people were once again in revolt . In an attempt to ease the volatile situation Florestan ceded power to his son Charles , but this came too late to appease the Monégasques . Menton and Roquebrune broke away from Monaco , leaving the Grimaldi ' s already small country hugely diminished — little more than Monte Carlo . Florestan died in 1856 and his son , Charles , who had already been ruling what remained of Monaco , succeeded him as Charles III ( " Illustration 15 " ) . Menton and Roquebrune officially became part of France in 1861 , reducing Monaco ' s size at a stroke by 80 % . With time on his hands , Charles III now devoted his time to completing the restoration of his palace begun by his uncle Honoré V . He rebuilt St Mary ' s Tower ( " Illustration 14 " ) and completely restored the chapel , adding a new altar , and having its vaulted ceiling painted with frescoes , while outside the façade was painted by Jacob Froëschle and Deschler with murals illustrating various heroic deeds performed by the Grimaldi . The Guard Room , the former great hall of the fortress ( now known as the State Hall ) , was transformed by new Renaissance decorations and the addition of a monumental chimneypiece . Charles III also made serious attempts to find the various works of art and furniture looted , sold and dispersed during the revolution . Together with new purchases , a fine art collection once again adorned the palace which included not only family portraits such as that of Lucien I by de Predis ; Honoré II by Philippe de Champaigne ; the head of Antoine I by Hyacinthe Rigaud , and van Loo ' s portrait of Louise - Hyppolyte ( " Illustration 11 " ) but also such masterpieces as the " The Music Lesson " by Titian . Charles III was also responsible for another palace in Monte Carlo , one which would fund his restorations , and turn around his country ' s faltering economy . This new palace was Charles Garnier ' s Second Empire casino , completed in 1878 ( " Illustration 16 " ) . The first Monaco casino had opened the previous decade . Through the casino Monaco became self - supporting . Decline of Grimaldi power . By the time of Charles III ' s death in 1889 , Monaco and Monte Carlo were synonymous as one and the same place , and had acquired , through gambling , a reputation as a louche and decadent playground of the rich . It attracted everyone from Russian grand dukes and railway magnates , often with their mistresses , to adventurer s , causing the small country to be derided by many including Queen Victoria . In fact so decadent was Monaco considered that from 1882 , when she first began visiting the French Riviera , Queen Victoria refused to make a courtesy social call at the palace . The contemporary writer Sabine Baring - Gould described the habituées of Monaco as : " . . . the moral cesspool of Europe . " The successive rulers of Monaco tended to live elsewhere and visit their palace only occasionally . Charles III was succeeded in 1889 by Albert I . Albert married the daughter of a Scottish aristocrat . The couple had one son , Louis , before divorcing in 1880 . Albert was a keen scientist and founded the Oceanographic Institute in 1906 ; as a pacifist he then founded the International Institute of Peace in Monaco . Albert ' s second wife , Alice Heine , did much to turn Monte Carlo into a cultural centre , establishing both ballet and the opera in the city . Having brought a large dowry into the family she contemplated turning the casino into a convalescent home for the poor who would benefit from recuperation in warm climes . The couple separated before she was able to put her plan into action . In 1910 , the palace was stormed during the Monegasque Revolution . The prince pronounced an end to absolute monarchy by promulgating a constitution with an elected parliament the following year . Albert was succeeded in 1922 by his son Louis II . Louis II had been brought up by his mother and stepfather in Germany , and did not know Monaco at all until he was 11 . He had a distant relationship with his father and served in the French Army . While posted abroad , he met his mistress Marie Juliette Louvet , by whom he had a daughter , Charlotte Louise Juliette , born in Algeria in 1898 . As Prince of Monaco , Louis II spent much time elsewhere , preferring to live on the family estate of Le Marchais close to Paris . In 1911 Prince Louis had a law passed legitimising his daughter so that she could inherit the throne , in order to prevent its passing to a distant German branch of the family . The law was challenged and developed into what became known as Monaco succession crisis . Finally in 1919 the prince formally adopted his illegitimate daughter Charlotte , who became known as Princess Charlotte , Duchess of Valentinois . Louis II ' s collection of artefacts belonging to Napoleon I form the foundation of the Napoleon Museum at the palace , which is open to the public . During World War II , Louis attempted to keep Monaco neutral , although his sympathies were with the Vichy French Government . This caused a rift with his grandson Rainier , his daughter ' s son , and the heir to Louis ' throne , who strongly supported the Allies against the Nazis . Following the liberation of Monaco by the Allied forces , the 75 - year - old Prince Louis did little for his principality and it began to fall into severe neglect . By 1946 he was spending most of his time in Paris , and on 27 July of that year , he married for the first time . Absent from Monaco during most of the final years of his reign , he and his wife lived on their estate in France . Prince Louis died in 1949 and was succeeded by his grandson , Prince Rainier III . Rainier III . Prince Rainier III was responsible for not only turning around the fortune and reputation of Monaco but also for overseeing the restoration of the palace . Upon his accession in 1949 Prince Rainier III immediately began a program of renovation and restoration . Many of the external frescoes on the courtyard were restored , while the southern wing , destroyed following the French revolution , was rebuilt . This is the part of the palace where the ruling family have their private apartments . The wing also houses the Napoleon Museum and the archives . The frescoes decorating the open arcade known as the Gallery of Hercules were altered by Rainier III , who imported works by Pier Francesco Mazzucchelli depicting mythological and legendary heroes . In addition many of the rooms were refurnished and redecorated . Many of the marble floors have been restored in the staterooms and decorated with intarsia designs which include the double R monogram of Prince Rainier III . Together with his wife , the late Grace Kelly , Prince Rainier not only restored the palace , but from the 1970s also made it the headquarters of a large and thriving business , which encouraged light industry to Monaco , the aim of which was to lessen Monaco ' s dependence on the income from gambling . This involved land reclamation , the development of new beaches , and high rise luxury housing . As a result of Monaco ' s increase in prestige , in 1993 it joined the United Nations , with Rainier ' s heir Prince Albert as head of the Monaco delegation . Princess Grace predeceased her husband , dying in 1982 as the result of a car accident . When Rainier III died in 2005 he left both his palace and his country in a stronger and more stable state of repair financially and structurally than they had been for centuries . The palace in the 21st century . Today the palace is home to Prince Rainier ' s son and successor , Prince Albert II . The state rooms are open to the public during the summer , and since 1960 , the palace ' s courtyard has been the setting for open air concerts given by Monte - Carlo Philharmonic Orchestra ( formerly known as the Orchestra of the National Opera ) . However , the palace is far more than a tourist attraction and museum : it remains a fully working palace and headquarters of the Monégasque ruler , a fact emphasised by the sentries on constant guard duty at the entrance ( " Illustration 17 " ) . The sovereign princes , although bound by constitution , are involved with the day to day running of Monaco as both a country and a business . Today Monaco covers an area of of which 40 ( 99 acres ) have been reclaimed from the sea since 1980 . For important Monégasque events — such as Grimaldi weddings and births — the palace courtyard is opened and the assembled citizens of Monaco are addressed by the prince from the Gallery of Hercules overlooking the courtyard . The courtyard is also used to host the annual children ' s Christmas party . Through such events , the palace continues to play a central role in the lives of the prince and his subjects , as it has done for over 700 years .