The apocalyptic laughter of Shiva is referred as Attahasa.
Some scholars are of the view that this a future manifestation of Shiva.
Shiva took the form of Attahasa in a mountain in the Himalayan Range.The sons of Shiva will also reside in the Attahasa mountain range in the 20th yuga.-Vayu Purana.
However in the center there are no permanent structures except the main temple and the water tank – the associated Shiva temple is a couple of hundred meters away, close to the entrance to the temple complex.
The Shivalingam is made of hard black stone & worshipped by the name of Shambhu aka Ruru Bhairav.
The Lingam appears to be buried – it is situated in a pit with the chamber’s marble interiors surrounding it on all sides
The lingam was once complete & protruding from the ground like normal Shivalingams.
It was broken base upwards by a Muslim soldier named Kalapathar (literally “Black stone”, perhaps referring to his physical strength or his stone-
heartedness) when Bengal was ruled by the Pathan warlord Sulaiman Khan Karrani.