Ancient Rome has been brought back to life through a unique digital reconstruction project, said to be the world's biggest computer simulation.
Tourists can use the model to prepare for visits to Roman ruins
An international team of architects, archaeologists and experts spent 10 years working on a real-time 3D model of the city called Rome Reborn.
Some 7,000 buildings were scanned and reproduced using a model of the city kept at a Rome museum.
Users enter the city at the time of Constantine and see inside buildings.
The simulation takes place in AD320, which is said to be the city's peak, when it had grown to a million inhabitants.
"We can take people under the Colosseum and show them how the elevators worked to bring the animals up from underground chambers for the animal hunts they held," said Bernard Frischer, the project's leader who heads Virginia's Institute for Advanced Technology in the Humanities.
The simulation reconstructs the interior of about 30 buildings - including the Senate, the Colosseum and the basilica built by the emperor Maxentius - complete with frescoes and decorations.
The project brought together experts from the University of Virginia and the Los Angeles branch of the University of California, as well research institutes in Italy, Germany and the UK.
To create the simulation, digital images were taken of the vast Plastico di Roma Antica model kept at the Museum of Roman Civilisation as well as laser scans of Rome today.
A panel of archaeologists also advised on how statues and monuments would look if they had not been darkened by pollution.
In addition, ancient maps and building catalogues detailing "apartment buildings, private houses, inns, storage facilities, bakeries and even brothels" were used, Mr Frischer said.
The project will be used to carry out further research into ancient Rome's way of life and will be updated according to new archaeological discoveries.
"This is the first step in the creation of a virtual time machine, which our children and grandchildren will use to study the history of Rome and many other great cities around the world," he said.
"For example, in scholarly literature the Colosseum has a great reputation for being a great people mover where people could find their seats very quickly. But estimates of the carrying capacity vary wildly from 35,000 to 78,000," he said.
Talks are said to have begun with Linden Labs to make the entire simulation available on the internet through the company's virtual world Second Life.
The 3D animations based on the simulation will eventually be made available to tourists to prepare them for their visit to the Colosseum, the Forum, or the imperial palaces on the Palatine.