The collection was opened to public in 1889 and since then it has been housed in the building of former City Hall and loggia. It is a Renaissance building from the first half of the 15th century. Other public buildings in the main square, the Bishop's Palace and the Cathedral, date from the same period. The building has been protected as the monument of culture since 1964. The Lapidarium is situated inside a spacious loggia, together with the ancient stone fragments, medieval wicker ornaments and the Renaissance spolias, while the items predominantly from the period of the Early Roman Empire have been displayed on the first floor of the City Hall.