Valletta, Malta Ruled successively by the Phoenicians, Greeks, Carthaginians, Romans, Byzantines, Arabs and the Order of the Knights of St. John, the latter of which was responsible for building the city in the 16th century, Valletta is one of the world's rare urban inhabited sites that has been preserved near perfectly. Crammed into a tiny fortified peninsula, the site comprises 320 monuments, making it one of the most concentrated historic areas in the world.