This gate, similar to the lost Gates of Tashkent, is located in Itchan Kala in Khiva, Uzbekistan. Since 1990, it has been protected as the World Heritage Site. The old town retains more than 50 historic monuments and 250 old houses, dating primarily from the eighteenth or nineteenth centuries. Djuma Mosque, for instance, was established in the tenth century and rebuilt from 1788 to 1789, although its celebrated hypostyle hall still retains 112 columns taken from ancient structures. The most spectacular features of Itchan Kala are its crenellated brick walls and four gates at each side of the rectangular fortress. Although the foundations are believed to have been laid in the tenth century, present-day 10-metres-high walls were erected mostly in the late seventeenth century and later repaired.