Ancona, city, central Italy, capital of Ancona Province and of Marche Region, a seaport on the Adriatic Sea. It is a busy commercial and fishing port. Other industries include shipbuilding, petroleum refining, and the manufacture of sugar, sailcloth, paper, chemicals, machinery, and musical instruments. Ancona was founded about 390 BC by Greek merchants from Syracuse. The city later became a Roman colony. It was used as a Roman naval station during the Illyrian War in 178 BC, and it was captured by Julius Caesar after he crossed the Rubicon in 49 BC.