Alexandria Troas ("Alexandria of the Troad"; Greek: Αλεξάνδρεια Τρωάς; Turkish: Eski Stambul, "Old Istanbul") is the site of an ancient Greek city situated on the Aegean Sea near the northern tip of Turkey's western coast, the area known historically as Troad, a little south of Tenedos (modern Bozcaada).

The site sprawls over an estimated 400 hectares (990 acres); among the few structures remaining today are a ruined bath, an odeon, a theatre, gymnasium complex[1] and a recently uncovered stadion.

As the chief port of north-west Asia Minor, the place prospered greatly in Roman times, becoming a "free and autonomous city" as early as 188 BC,[4] and the existing remains sufficiently attest its former importance.

In the 10th century Troas is given as a suffragan of Cyzicus and distinct from the famous Troy (Heinrich Gelzer, Ungedruckte ... Texte der Notitiae episcopatuum, 552; Georgii Cyprii descriptio orbis romani, 64); it is not known when the city was destroyed and the diocese disappeared.

[1] The site's stones were much plundered for building material (for example Mehmed IV took columns to adorn his Yeni Valide Mosque in Istanbul).

[15] Remains of an ancient bath and gymnasium complex can be found within this area; this building is locally known as Bal Saray (Honey Palace) and was originally endowed by Herodes Atticus in the year 135.