Piazza Colonna

Lonely Planet review

Dominating the northern side of this stylish piazza, Palazzo Chigi (06 677 93 417; www.governo.it in Italian; Piazza Colonna 370; visits on request) has been the official residence of the Presidente del Consiglio, Italy's prime minister, since 1961. The building, off limits unless you've booked a visit, was started in the 16th century by Matteo di Castello and finished more than a 100 years later by Felice della Greca.

In the centre of the piazza is the 30m-high Colonna di Marco Aurelio. Inspired by the Colonna di Traiano in the Imperial Forums, it was completed in AD 193 to honour Marcus Aurelius' victories in battle. The vivid reliefs on the lower part depict scenes from battles against the Germanic tribes (AD 169-173), while those further up commemorate the war against the Sarmatians (AD 174-176). In 1589 Marcus was replaced on the top of the column with a bronze statue of St Paul.

South of the piazza, in Piazza di Pietra, is the Tempio di Adriano. Eleven huge Corinthian columns, now embedded in what used to be the Roman stock exchange, are all that remain of Hadrian's 2nd-century temple.