Koi Krylgan Kala (Uzbek: Qoʻyqirilgan qalʼa; Russian: Кой-Крылган-Кала) is an archaeological site located outside the village of Taza-Kel'timinar in the Ellikqal'a District (Uzbek: Ellikqalʼa tumani; Russian: Элликкалинский район) in the Republic of Karakalpakstan, an autonomous republic of Uzbekistan. In ancient times, it was sited along a canal in the Oxus delta region.

There is some relationship between Koi Krylgan Kala and Toprak-Kala, 30 km to the northwest. It is a temple complex of the Chorasmian Dynasty, an Iranian people who ruled the area of Khwarezm. It was built in the 4th-3rd century BCE. The Apa-Saka tribe destroyed it c. 200 BCE, but later it was rebuilt into a settlement, which lasted until c. 400 CE. It was discovered in 1938 by Sergey Pavlovitch Tolstov, leader of the Chorasmian Archaeological-Ethnological Expedition. It contained a Mazdian fire temple and was decorated with frescos of wine consumption.

The explorer Sergey Tolstov drew a reconstruction of the ancient fortress.

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  Statue of a man-ossuary from Koi Krylgan Kala, first centuries A.D., Hermitage Museum
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  Location of the Koi Krylgan Kala fortress in the Chorasmian oasis, in relation to other main fortresses

• Yar-Shater, Ehsan (1983). The Cambridge history of Iran. Cambridge University Press. pp. 1488 pages. ISBN 0-521-24693-8.

• Eduljee, K. E. (2007). "Zoroastrian Heritage". Heritage Institute. Retrieved 27 July 2009.