Pothgul Viharaya is an old library and monastery in the Polonnaruwa district of Sri Lanka. The ruins of this ancient library date back to the twelfth century. The name Pothgul itself means ‘Bookstore’.The library was as a place to store Buddhist books built with bricks, but now it is nothing but a demolished historic site. It was once part of a monastery and provide shelter to resident monks. It was thought to be a Buddhist library complex where Buddhist writings were studied. It is situated next to a beautiful lake where tourists can enjoy boating.