Horse A horse was a large mammal native to the planet Earth . It was used for transportation , sport and companionship . So intertwined were horses with human s , that horses were the bases for many cultural references . As transportation . Human s used horses as transportation for thousands of years . They could be directly mounted or used to pull vehicles . ( TV : " The King ' s Demons " , " The Unquiet Dead " ) As mounts . In 323 BC , Alexander the Great taught Ian Chesterton how to ride a horse . ( AUDIO : " The Time Museum " ) When visiting the Roman Empire in 120 AD , the Tenth Doctor once sought horses for transport because he deemed them " better " — which was to say " faster " — than donkey s . ( PROSE : " The Stone Rose " ) Around the same time , the Eleventh Doctor , Amy Pond and River Song used Roman horses to cover the distance to Stonehenge . ( TV : " The Pandorica Opens " ) In 1006 , King Sitric Silkbeard of Dublin rode his horse Sleipnir , to whom he often spoke as if he were a person , on a three day journey from Dublin to the Abbey of Kells to retrieve the Book of Kells . ( AUDIO : " The Book of Kells " ) In 1207 , the Eleventh Doctor rode a horse from the monastery in Cumbria to the cave where his TARDIS was hidden . ( TV : " The Bells of Saint John " ) On 4 March 1215 , Geoffrey de Lacy rode his horse from London to find John of England ' s castle . The journey took him only four hours . Horses were also used in a javelin match in the 13th century to settle arguments . They were very popular modes of transport . ( TV : " The King ' s Demons " ) The Eleventh Doctor once rode a horse through 17th century Coventry . ( WC : " Pond Life " ) As beasts of burden . Horses could be used to pull vehicles , such as chariot s ( TV : " The War Games " ) , carriage s ( TV : " The Unquiet Dead " , COMIC : " Highway Robbery " , AUDIO : " The Doomwood Curse " , TV : " The Visitation " , " The Snowmen " , " The Crimson Horror " ) stagecoach es ( PROSE : " The Many Hands " ) , wagons ( TV : " The Mark of the Rani " ) and hansom cab s ( TV : " The Evil of the Daleks " , " The Talons of Weng - Chiang " ) In sport . Horses were also used — at least in England — as mounts in jousting tournaments . ( TV : " The King ' s Demons " ) Other . According to Marco Polo , horses were able to sense oncoming sandstorm s . ( TV : " The Singing Sands " ) Horses and the Doctor . The Doctor was an adept horseman in many incarnations . The Fourth Doctor had no difficulty jumping on to the backs of unsaddled horses in San Martino in 1492 and galloping away from the threat of execution . ( TV : " The Masque of Mandragora " ) He would later ride to Olympus in a flying - horse - drawn chariot with Prometheus . ( COMIC : " The Life Bringer " ) The Sixth Doctor once rode on a horse in an attempt to catch up with Astrolabus . ( COMIC : " Once Upon a Time Lord " ) In his eighth incarnation , the Doctor and Izzy Sinclair spent some time in feudal Japan , where they both travelled by horse . ( COMIC : " The Road to Hell " ) Later , the Eighth Doctor spent time riding with the Lakota Sioux . ( COMIC : " Bad Blood " ) While on board the SS " Madame de Pompadour " in the 51st century , the Tenth Doctor came across a horse he called Arthur , which had presumably crossed over through a time window from the 18th century . It followed him around the ship for a while , but Rose forbade him to keep it . He later skilfully rode Arthur through a time window disguised as a high mirror , breaking the system the Clockwork Droid s had built . Arthur was thus instrumental to freeing Madame de Pompadour from the Droids . He was left back in the 18th century by the Doctor , where Arthur was meant to live . ( TV : " The Girl in the Fireplace " ) He later rode another white horse when he took Elizabeth I to see his TARDIS in 1562 . During a picnic , a reaction on his detector led the Doctor to believe that the Queen was a Zygon in disguise , only to find out the Zygon had taken the form of the horse instead . ( TV : " The Day of the Doctor " ) Later in his life , the Doctor ' s eleventh incarnation showed considerable prowess with horses not only at Stonehenge in the 2nd century AD , ( TV : " The Pandorica Opens " ) but also on the American frontier . ( TV : " A Town Called Mercy " , AUDIO : " The Runaway Train " ) Amy Pond was also particularly adept at riding horses and was able to keep up with the Eleventh Doctor when they rode together . She even rode a horse on Olympus amongst the gods . ( COMIC : " The Chains of Olympus " ) The Eleventh Doctor also claimed to be able to speak horse , conversing with a horse named Susan in Mercy in 1870 . ( TV : " A Town Called Mercy " ) Cultural references to horses . One of the longest - standing cultural references to horses on Earth was that of the " Trojan Horse " . Aware of this reference from history , the First Doctor then in turn suggested the idea to the Greek army that they build a giant wooden statue of a horse and presented it to Troy . Unbeknownst to the Trojans , the Greeks had secreted themselves inside the moveable statue and sprang a decisive attack upon the Trojans once they were behind Trojan walls . This move ended the Trojan War in favour of the Greeks . ( TV : " The Myth Makers " ) Horses were a common adornment of fairground carousel s . Once , the Eighth Doctor thought that the TARDIS ' chameleon circuit had accidentally started working in Nazi Germany , turning the police box into a carousel . Testing the new shape , Lucie alighted one of the fake horses and engaged the wheel . The Doctor quickly concluded the TARDIS had not in fact changed into a carousel . ( AUDIO : " The Scapegoat " ) In English , " horse " sounded similar to the word " host " . This resulted in the Jixen warrior , Jixey , referring to himself as a horse when he made a mistake after just having learnt English . He intended to inform Starkey that he was his host . ( TV : " Hound of the Korven " )