Among European cathedrals, Split has the oldest building - the mausoleum of the Roman emperor Diocletian. In it, at the end of the second millennium, history reconciles pagan ancient, Christian medieval and modern heritage. In the middle of the 7th century, the mausoleum of the Christian persecutor became a cathedral with altars with relics of St. Domnius and St. Stas, martyrs executed in nearby Solin. The cathedral bell tower (57 m) is the most original Dalmatian medieval building from the 13th century. At the turn of the 19th and 20th centuries, the bell tower was thoroughly renovated and slightly altered. Today, it is possible to climb the stairs to the top of the bell tower, which offers a spectacular view of the whole of Split.