 Genoese and to a lesser extent Venetian traders regularly came to Trabzon.To secure their part of the Black Sea trade, the Genoese bought the coastal fortification "Leonkastron", just west of the winter harbour, in the year 1306.One of the most famous persons to have visited the city in this period was Marco Polo, who ended his overland return journey at the port of Trebizond, and sailed to his hometown Venice with a ship; passing by Constantinople (Istanbul) on the way, which was retaken by the Byzantines in 1261.