Assos

a sea-port town of Proconsular Asia, in the district of Mysia, on the north shore of the Gulf of Adramyttium. Paul came hither on foot along the Roman road from Troas (Acts 20:13; 20:14), a distance of 20 miles. It was about 30 miles distant from Troas by sea. The island of Lesbos lay opposite it, about 7 miles distant.

EBD - Easton's Bible Dictionary