A tour of the fortifications is an excellent occasion to admire the harmonious façades and incomparable roofs of round tiles that are at the heart of Dubrovnik's reputation. It also provides a chance to get a closer look at the town's defensive system, of which the most remarkable elements are the Fort of St John, the harbour defences (tvrdava sv. Ivan) and the inland fortifications and Minceta tower (tvrdava Minceta).