why is the city of pompeii important to the study of roman art?
There is much evidence of the grand scale of art and magnificent architecture that once existed in the city as some of its ruins still remain today, such as the Arch of Caligula, as well as buildings of great political social and commercial significance, including as the Forum that once stood central in this city.
Pompeii and many other Roman cities also owned a different genre of grand buildings. The primary purposes of such buildings were to provide entertainment for the Romans who belonged to a society that craved excitement and thrived from thrilling entertainment experiences. Buildings known as amphitheatres were built exactly for the purpose of entertaining a grand Roman audience.
The city became an important passage for goods that arrived by sea and had to be sent toward Rome or southern Italy along the nearby Appian Way. Many public buildings were built or refurbished and improved under the new order; new buildings included the amphitheatre in 70 BC, the Forum Baths and the theatrum tectum while the forum was embellished with the colonnade of Popidius before 80 BC.  These buildings raised the status of Pompeii as a cultural centre in the region as it outshone its neighbours in the number of places for entertainment which significantly enhanced the social and economic development of the city.
Weathering, erosion, light exposure, water damage, poor methods of excavation and reconstruction, introduced plants and animals, tourism, vandalism and theft have all damaged the site in some way. The lack of adequate weather protection of all but the most interesting and important buildings has allowed original interior decoration to fade or be lost. Two-thirds of the city has been excavated, but the remnants of the city are rapidly deteriorating. 
Much research has centered on public buildings and breathtaking villas that portray the artistic and opulent lifestyle enjoyed by the city’s wealthy elite.
“We’re trying to see how the other 98 percent of people lived in Pompeii,” Ellis says. “It’s a humble town block with houses, shops, and all the bits and pieces that make up the life of an ancient city.”
These records can be used to print physical replicas in 3D – even full-scale models that could be opened to tourists, while the real ruins are saved for posterity. Such a replica has recently been completed of Tutankhamun’s burial chamber, to stunning effect.
The body casts at Pompeii are justly famous, but it is the skeletons themselves that are now proving to be the more informative. Studies that include medical scanning of casts, and searches of centuries of museum collections have shown it was not just the weak and infirm who failed to escape Vesuvius’s wrath. In just one house, 13 healthy people died: their ages suggest grandparents, parents and their children, one of whom was a pregnant teenager.
Pompeii supported between 10,000 and 20,000 inhabitants at the time of its destruction. The modern town (comune) of Pompei (pop.  25,440) lies to the east and contains the Basilica of Santa Maria del Rosario, a pilgrimage centre.
The remains of Pompeii’s city walls are 2 miles (3 km) in circumference, and they enclose an area of about 163 acres (66 hectares). Several city gates have been excavated. There are many remains of public buildings, generally grouped in three areas: the Forum, located in the large level area to the southwest; the Triangular Forum, standing on a height at the edge of the south wall overlooking the bay; and the Amphitheatre and Palaestra, in the east. Hundreds of private homes of various architectural styles have also been excavated at Pompeii.