Ulcinj Old Town (Serbian: Стари град Улцињ / Stari grad Ulcinj; Albanian: Qyteti i vjetër i Ulqinit) or Ulcinj Castle (Serbian Cyrillic: Калjаја; Albanian: Kalaja e Ulqinit) is an ancient castle and neighborhood in Ulcinj, Montenegro. Today mostly inhabited by Albanians, it was built by the Illyrians on a small peninsula at the right side of the Pristan Gulf, which is part of the Adriatic Sea. Today, oldest remains are the Cyclopean Wall. The castle has been restored many times since it was first built although major changes were made by the Byzantinians, Serbs, Venetians, and Ottomans. The modern city of Ulcinj was built outside of this castle.