A Bishop's Library Mussenden Temple sits on the edge of the 120’ cliff overlooking Castlerock Beach. It was once possible to drive a horse and carriage around the building but the forces of nature over the years has brought it closer and closer to the edge. It served as the Bishop’s library and the library’s walls were once lined with bookcases. A fire was kept constantly burning in the basement and an enclosed flue ensured the books never got damp even in this exposed location. Mussenden Temple is located near Castlerock on the coast of Northern Ireland.