Siege of Velyaminovsky
1840 CE.
Shown on the map at 44.097°, 39.072°.
The Siege of Velyaminovsky (Adyghe: ТIопсэ зау; Russian: Оборона Вельяминовского форта) took place on the night of 12 March 1840 (29 February O.S.) during the Russo-Circassian War. The Circassians attacked the fort after the morning prayer, and seven and a half hours later, the fort fell.
Text from the Wikipedia article Siege of Velyaminovsky, licensed CC BY-SA 4.0.