The eastern region of the Subcontinent, the states of Bihar, West Bengal, Orissa, Assam, the adjoining hill states and the country of Bangladesh (previously East Bengal) are less prosperous than western India, but rich in a culture that has a very ancient history. Bihar and West Bengal are densely populated areas of flat plains traversed by the river Ganges, which spread north to the foothills of the Himalayas. Orissa is a largely unspoiled state of farming villages with a relatively small population, best known for the great religious centre of Puri and the ancient temples of Bhubaneswar and Konark. In the past it was isolated from the rest of India by the thick forests of its hills.