Adam Clarke on Acts 16:8

Came down to Troas - The Troad, or part of Phrygia Minor in which the celebrated city of Troy was formerly situated. This city was first built by Dardanus, who was its king, and from whom it was called Dardania; from Tros, his grandson, it was called Troja, or Troy; and from his son, Ilus, it was called Ilium. It has been long so completely destroyed that no ascertainable vestige of it remains; insomuch that some have even doubted of its existence. Those who contend for the reality of the history of Troy suppose it to have stood on the site of the modern village Bounarbachi, about twelve miles from the sea, on an eminence, at the termination of a spacious plain.