Question: Which emperor started the construction of Colosseum?
About the article "Colosseum", section "Abstract".

Candidate passages:
Construction of the amphitheatre.
Construction of the Colosseum started under Vespasian in an area on the floor of a low valley between the Caelian, Esquiline and Palatine hills.
The site had been devastated by the Great Fire of Rome in AD 64 under the Emperor Nero and later redeveloped for his personal enjoyment with the construction of a huge artificial lake, Domus Aurea, and a colossal statue of himself.
Vespasian started his own redevelopment of the site around AD 70 to 72, possibly funding the construction with booty seized after the Roman victory in the First Jewish-Roman War in AD 70.
The lake was filled and the site designated as the location for the Flavian Amphitheatre.
By reclaiming the land appropriated by Nero for the site for his amphitheatre, Vespasian at once made both a popular gesture and placed a symbol of his power at the heart of the city.
Gladiatorial schools ("ludi") and other support buildings were later constructed within the former grounds of the Domus Aurea, much of which had been torn down.
Vespasian died just before the amphitheatre was completed.
The building had reached the third story and Titus was able to finish construction of both the amphitheatre and adjacent public baths (which were to be known as the Baths of Titus) within a year of Vespasian's death. 
The Premio Colosseo is a prize awarded to a person who has enhanced the image of the city of Rome.
It was inaugurated in 2009, the 2000th anniversary of the birth of emperor Vespasian, builder of the Colosseum.
The award is a silver model of the Colosseum. 
Colosseum is the annual Inter-Collegiate technical festival of the college held after Odyssey. 
Construction of the Colosseum began under the rule of the Emperor Vespasian in around 70–72 AD, funded by the spoils taken from the Jewish Temple after the Siege of Jerusalem.
The site chosen was a flat area on the floor of a low valley between the Caelian, Esquiline and Palatine Hills, through which a canalised stream ran.
By the 2nd century BC the area was densely inhabited.
It was devastated by the Great Fire of Rome in AD 64, following which Nero seized much of the area to add to his personal domain.
He built the grandiose "Domus Aurea" on the site, in front of which he created an artificial lake surrounded by pavilions, gardens and porticoes.
The existing "Aqua Claudia" aqueduct was extended to supply water to the area and the gigantic bronze Colossus of Nero was set up nearby at the entrance to the Domus Aurea.
Although the Colossus was preserved, much of the Domus Aurea was torn down.
The lake was filled in and the land reused as the location for the new Flavian Amphitheatre.
Gladiatorial schools and other support buildings were constructed nearby within the former grounds of the Domus Aurea.
According to a reconstructed inscription found on the site, "the emperor Vespasian ordered this new amphitheatre to be erected from his general's share of the booty."
This is thought to refer to the vast quantity of treasure seized by the Romans following their victory in the Great Jewish Revolt in 70 AD.
The Colosseum can be thus interpreted as a great triumphal monument built in the Roman tradition of celebrating great victories, placating the Roman people instead of returning soldiers.
Vespasian's decision to build the Colosseum on the site of Nero's lake can also be seen as a populist gesture of returning to the people an area of the city which Nero had appropriated for his own use.
In contrast to many other amphitheatres, which were located on the outskirts of a city, the Colosseum was constructed in the city centre; in effect, placing it both literally and symbolically at the heart of Rome.
The Colosseum had been completed up to the third story by the time of Vespasian's death in 79.
The top level was finished and the building inaugurated by his son, Titus, in 80.
Dio Cassius recounts that over 9,000 wild animals were killed during the inaugural games of the amphitheatre.
Commemorative coinage was issued celebrating the inauguration.
The building was remodelled further under Vespasian's younger son, the newly designated Emperor Domitian, who constructed the "hypogeum", a series of underground tunnels used to house animals and slaves.
He also added a gallery to the top of the Colosseum to increase its seating capacity.
In 217, the Colosseum was badly damaged by a major fire (caused by lightning, according to Dio Cassius) which destroyed the wooden upper levels of the amphitheatre's interior.
It was not fully repaired until about 240 and underwent further repairs in 250 or 252 and again in 320.
An inscription records the restoration of various parts of the Colosseum under Theodosius II and Valentinian III (reigned 425–455), possibly to repair damage caused by a major earthquake in 443; more work followed in 484 and 508.
The arena continued to be used for contests well into the 6th century, with gladiatorial fights last mentioned around 435.
Animal hunts continued until at least 523, when Anicius Maximus celebrated his consulship with some "venationes", criticised by King Theodoric the Great for their high cost. 
  In the scene with the gladiator caravan coming into Rome, a wall that surrounds the entire city can be seen, which resembles the Aurelian Wall.
The Aurelian Wall was not made until 275 A.D.
In the film it is stated that the Colosseum holds 50,000 people.
It is now believed to have seated 73,000.
In the movie, the Colosseum is referred to by that name; in truth during the Roman Empire it was known as the Flavian Amphitheatre (Latin: Amphitheatrum Flavium).
The name "Colosseum", derived from the Latin word "colosseus" meaning colossal in reference to the broken remains of a giant statue of the Emperor Nero found there, came into common use around the 10th century.
After visiting the Colosseum, Ridley Scott thought it was too small so the one in the film is larger than the real Colosseum.
In the film most Roman architecture is portrayed as being white.
Historical excavations and archaeologists often say that this is a misconception, as most buildings and structures were somewhat coloured, and that we only believe this because what we find from Roman time (and even Greek) often look white.
This is only because the original colour, through the ages, has gradually disappeared and left structures and buildings white.