Pantheon

The Pantheon is the best-preserved building of ancient Rome and one of the most influential structures in the history of architecture, standing almost intact in the Piazza della Rotonda in the city's historic centre. Rebuilt by Emperor Hadrian around 125 AD on the site of an earlier temple by Agrippa, whose name still runs in bronze letters across the portico, it was a temple to all the gods and has been in continuous use since the 7th century as the church of Santa Maria ad Martyres. Visitors pass beneath sixteen towering monolithic granite columns shipped from Egypt, push through the original bronze doors, and step into the single great rotunda. The interior is a perfect sphere: the height to the top of the dome equals its 43.3-metre diameter, and at the crown an open circular oculus nearly nine metres across is the building's only source of light. The shaft of sunlight it admits moves around the coffered concrete dome through the day like a slow sundial, and on rainy days water falls straight through to drain away through holes in the sloping marble floor. The unreinforced concrete dome remains the largest of its kind ever built. Around the walls are the tombs of the Renaissance painter Raphael and of the first kings of unified Italy, Vittorio Emanuele II and Umberto I. A visit takes about 45 to 60 minutes. Since 2023 a modest timed-entry ticket is required, and booking online avoids the queue that forms across the piazza by mid-morning. The space is busiest late morning and midday; early opening and the last hour are calmer, and rainy days reward patient visitors with the famous shaft of falling rain. Photography is freely allowed, and the best images catch the oculus beam striking the dome. Free, beautiful and astonishingly old, the Pantheon is among the essential sights of Rome.