As noted earlier, the Palas built a number of monasteries and other sacred structures. The Somapura Mahavihara in present-day Bangladesh is a World Heritage Site. It is a monastery with 21 acre (85,000 m²) complex has 177 cells, numerous stupas, temples and a number of other ancillary buildings. The gigantic structures of other Viharas, including Vikramashila, Odantapuri, and Jagaddala are the other masterpieces of the Palas. These mammoth structures were mistaken by the forces of Bakhtiyar Khalji as fortified castles and were demolished. The art of Bihar and Bengal during the Pala and Sena dynasties influenced the art of Nepal, Burma, Sri Lanka and Java.