Split, in Italian Spalato, is a seaport, resort, and chief city of Dalmatia in Southern Croatia. It is situated on a peninsula in the Adriatic Sea with a deep, sheltered harbour on the South side. The city is best known for the ruins of the Palace of Diocletian (built 295–305 AD). Collectively with the historic royal residences, fortifications, and churches in the city, the palace was designated a UNESCO World Heritage site in 1979. From 812 Split developed as a major Byzantine city. In 1105, after brief incursions by Venice (998) and Croatia (1069), the city acknowledged the nominal suzerainty of Hungary-Croatia and fought sporadically with its rival Trogir. From 1420 to 1797 it was held by Venice. The Austrians ruled from 1797 to 1918 with a brief French interregnum in 1808-13.