The Pantheon is an ancient temple located in Rome, Italy. It was originally built by Marcus Agrippa in 27 BC as a temple to all the gods of ancient Rome. The current structure dates back to 120 AD, during the reign of Emperor Hadrian, who rebuilt the temple after a fire destroyed the original building.

The Pantheon is considered to be one of the best-preserved ancient buildings in Rome and is renowned for its architectural design. The building has a large domed roof, with an opening (oculus) at the top that provides natural light and ventilation. The dome is made of concrete and is the largest unsupported dome in the world, with a diameter of 43.3 meters (142 feet). The exterior of the Pantheon is made of brick and has a portico with large columns.

Inside the temple, visitors can see a circular chamber with a diameter of 43.3 meters (142 feet) and a height that is equal to its diameter. The walls of the chamber are decorated with marble and have alcoves with statues of different gods and goddesses. The oculus in the center of the dome provides a dramatic source of light that creates a unique and awe-inspiring atmosphere.

Over the centuries, the Pantheon has served different purposes, from being a temple to being used as a Christian church. Today, it is open to visitors and is one of Rome's most popular tourist attractions. It is also the final resting place of several notable individuals, including the painter Raphael and two Italian kings.