"Kamkinskaya" quarry or "Kiseli" (Kissels) - a system of artificial caves, quarries in the Moscow region. Here limestone was quarried for the construction of "white stone" in Moscow. Located not far from Moscow, near the village Kamkina. The length of the system is not certain, is about 10,5 - 12,0 km. Extraction was conducted mainly in the XVIII - XIX centuries. But probably
earlier, until the XVI century. Preserved, uneven areas, characterized by different methods of extraction (kolonniki, zabutovannye kolonniki, solid output). In the XX century, especially since the 60's, it has been a place of pilgrimage for tourists due to its underground informal subculture. Equipped grottoes, bas-relief images, drawings on the walls.