Rome

Rome was a city in Italy. It played an important role in Earth history, most notably as the centre of the Roman Empire, a large empire in early Human history.

Around the 5th century BC, the Cult of Demnos flourished in Italy. (DW: The Masque of Mandragora)

An alternative version of 41 BC Rome was created by the Rani, but with more advanced technology. (MA: State of Change)

The Doctor, Ian Chesterton, Barbara Wright and Vicki visited Rome in A.D.64. (DW: The Romans)

Rome was the new home of the Caecilius family after the destruction of Pompeii in A.D.79. (DW: The Fires of Pompeii)

A group of Roman soldiers was kidnapped by the War Lords for use in their war games (DW: The War Games)

In 1923 a British archaeological survey of Rome by professor Livesy-Smythe turned up a scroll by Caecilius telling of the true faith of Pompeii, first alerting Torchwood to the existence of the Pyroviles. (Captain Jack's Monster Files)

In an alternate 1970s Rome Magog was worshipped. (DWM: The Iron Legion)

In 2006 Rome was one of the many locations affected by the Sycorax's blood control, causing people to stand on the top of the Colosseum ready to jump. (DW: The Christmas Invasion)

In 2096, Rome was an independent city-state on a destitute Earth. (PDA: The Indestructible Man)

In the year 12005, the New Roman Empire flourished. (DW: The End of the World)
 * no further details are known, but it was presumably inspired by the original Roman Empire, and thus most likely had its capital in Rome.

Behind the scenes
In 2007, Rome's Cinecittà Studios played host to production of the episode The Fires of Pompeii; discounting some minor second unit work done for Daleks in Manhattan, this was the first Doctor Who adventure to be filmed outside the UK since Doctor Who in the 1990s.