What is "bars-hot"

Bars-Hot was city of Kidan, in the basin of the Kherlen River in eastern Mongolia. It occupied an area of 1600 by 1810 metres and was surrounded with mud walls, which are today 4 metres thick and 1.5–2 metres high. A remnant of a stupa is found near the walls. There used to be a pair of them, but in the 1940s the Soviet garrison used cannon fire to destroy one for amusement.