The Museum is situated inside the S. Sebastiano Gate of the Aurelian Walls and offers visitors an educational visit which was created in 1990, although the monument has been used in a more or less similar way since much earlier.
In 1939, despite the contrary inclination of the Office of the Distribution of Antiquities and Fine Arts, which opposed the transformation of the monument, which had for many years been open to the public, into an artistic studio, various works were carried out in the rooms inside the gate, to adapt it for use as a living place and private studio of Ettore Muti, the secretary of the fascist party, who stayed there from 1941 to 1943. New attics were created as the masonry vaults had collapsed, new rooms with dividing walls were created, staircases were installed in wood and masonry, and the floors were reworked in travertine and brick, with two mosaics inserted on the first floor.
After the second world war, the Gate was reopened to the public by the Municipality, which also started drafting a project to create a museum of the walls. During the years, however, and due to various events, some of the rooms in the Gate were used as service rooms for the guard and his family. The other rooms were given in 1960 for the use of the Ministry of Public Education and the General Board of Antiquities and Fine Arts, in order to install a special office on the Via Appia Antica and then a museum on the Via Appia; with this aim, various transformatory works were carried out in several of the bays, but the planned Office never came into existence. The municipal administration reclaimed the monument in 1970, the next year the Office of the Distribution of Antiquities and Fine Arts installed a small museum of the walls, connecting it to the section of the covered parapet circuit up to Via C. Colombo.
The museum was only open to the public on Sundays, and, after several years, unfortunately, it was once again completely closed; it was not until 1984 that the gate was definitively reopened and internally reordered, for the “Underground Rome” exhibition. In 1989 the Museum of the Walls of Rome was officially instituted on the decision of the Municipal Council, according to the Regional Law of 1975, and the following year the current educational displat opened.