Photograph of a general view of the valley at Loriyan Tangai, Peshawar taken by Alexander Caddy in 1896. The stupa at this site was excavated by the photographer and the sculptures found were removed and taken to the Indian Museum in Calcutta. Stupas are hemispherical monuments made of earth and usually encased in brick or stone. They are a focus of worship at Buddhist religious sites and from the first century AD onwards they became commonplace in Peshawar. At that time the Peshawar district of northern Pakistan was known as Gandhara and ruled by a group of Chinese origin known as the Kushans. They were Buddhists, and under their rule, the religion and the arts associated with it were allowed to flourish. The reign of the Kushan king Kanishka, is particularly well known for its architectural and artstic achievements. This period, usually dated to the second century AD, is associated with the Graeco-Roman influenced Gandharan sculpture and the construction of many Buddhist monasteries and stupas.