Qız qalası in the old town of Baku is a tower about 30m high built as a fortress in the 12th century. It is said that its foundation part dates back to BC. Also known as "Maiden's Tower". 
In 2000, it was registered as a World Heritage Site as "Walled City of Baku with the Shirvanshah's Palace and Maiden Tower".
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Pop-up card of Maiden Tower" 
(2021-01-16)