Ayaz-Kala is an archaeological site in Ellikqala District, Karakalpakstan, in northern Uzbekistan, built between the 4th century BCE and the 7th century CE. Situated on a hilltop overlooking the Kyzylkum Desert, the site encompasses the ruins of an ancient Khorezm fortress. The site consists of three fortresses which were built from the 4th century BCE to the 7th century CE. The fortresses were part of a series of forts at the edge of the Kyzylkum Desert, which provided defence against raids by nomads and the Saka of the Syr Darya delta. Part of Ayaz Kala was built in the second century by the Kushan Empire. The now-ruined fortress is speculated to have been built as part of a chain of border fortresses guarding the borders of the Kyzylkum Desert. In addition to the eroded remains of defensive works, the remnants of several residential structures have been uncovered at site. Ayaz Kala 1 is a fortress dating back to end of the 4th or beginning of the 3rd century BCE. Ayaz Kala 2 is a feudal fortress dating from the 6th to 8th century CE, in the Afrighid period. Ayaz Kala 3 is a fortified garrison dating from the 1st to 2nd century CE. The monumental building in the north east corner may have been founded in the 5th or 4th century BCE.