Museo delle Mura

The Museo delle Mura is an archaeological museum in Rome, Italy. It is housed in the first and second floors of the Porta San Sebastiano at the beginning of the Appian Way. It provides an exhibition on the walls of Rome and their building techniques, as well as the opportunity to walk along the inside of one of the best-preserved stretches of the Aurelian Wall. The museum is free of charge.

Source: Wikipedia