The pyramid was built about 18 BC-12 BC as a tomb for Gaius Cestius Epulo, a magistrate and member of one of the four great religious corporations at Rome, the Septemviri Epulonum. It is of brick-faced concrete covered with slabs of white marble standing on a travertine foundation, measuring 100 Roman feet (22 m) square at the base and standing 125 Roman feet (27 m) high. In the interior is the burial chamber, a simple barrel-vaulted rectangular cavity measuring 5.95 metres long, 4.10 wide and 4