Pantheon, temple dedicated to all the gods. The Pantheon of Rome is the best-preserved major edifice of ancient Rome and one of the most significant buildings in architectural history. In shape it is an immense cylinder concealing eight piers, topped with a dome and fronted by a rectangular colonnaded porch. The great vaulted dome is 43.2 m (142 ft) in diameter, and the entire structure is lighted through one aperture, called an oculus, in the center of the dome. The Pantheon was erected by the Roman emperor Hadrian between AD 118 and 128, replacing a smaller temple built by the statesman Marcus Vipsanius Agrippa in 27 BC. In the early 7th century it was consecrated as a church, Santa Maria ad Martyres, to which act it owes its survival (see Architecture). The term pantheon also refers to a building that serves as a mausoleum or memorial for eminent personages of a country. The most famous example is the Church of Sainte Geneviève in Paris, designed (1764) in the classical style by the French architect Jacques Germain Soufflot. It was later secularized, renamed the Pantheon, and used as a temple to honor the great of France. Built in Rome, AD c.118-28, in the reign of Emperor Hadrian, the Pantheon is the best preserved and most impressive of all Roman buildings. It has exerted an enormous influence on all subsequent Western architecture. The Pantheon asserts the primacy of space as contained volume over structure in the most dramatic fashion. From the time of the Pantheon onward, Roman architecture was to be one of spatial volumes. The Pantheon was designed and built by Hadrian to replace an earlier temple established by Agrippa (the misleading inscription in the entrance frieze refers to this earlier edifice). The existing structure is an immense round temple covered by a single dome, fronted by a transitional block and a traditional temple portico of eight Corinthian columns carrying a triangular pediment.