Sarnath is a place located 10 kilometres north-east of Varanasi near the confluence of the Ganges and the Varuna rivers in Uttar Pradesh, India. The deer park in Sarnath is where Gautama Buddha first taught the Dharma, and where the Buddhist Sangha came into existence through the enlightenment of Kondanna.

Singhpur, a village approximately one kilometre away from the site, was the birthplace of Shreyansanath, the Eleventh Tirthankara of Jainism. A temple dedicated to him, is an important pilgrimage site.

Also referred to as Isipatana, this city is mentioned by the Buddha as one of the four places of pilgrimage to which his devout followers should visit. It was also the site of the Buddha's Dhammacakkappavattana Sutta, which was his first teaching after attaining enlightenment, in which he taught the four noble truths and the teachings associated with it.

Sarnath has been variously known as Mrigadava, Migadāya, Rishipattana and Isipatana throughout its long history. Mrigadava means "deer-park". "Isipatana" is the name used in the Pali Canon, and means the place where holy men (Pali: isi, Sanskrit: rishi) landed.

The legend says that when the Buddha-to-be was born, some devas came down to announce it to 500 rishis. Another explanation for the name is that Isipatana was so called because, sages, on their way through the air (from the Himalayas), alight here or start from here on their aerial flight. Pacceka Buddhas, having spent seven days in contemplation in the Gandhamādana, bathe in the Anotatta Lake and come to the habitations of men through the air, in search of alms. They descend to earth at Isipatana. Sometimes the Pacceka Buddhas come to Isipatana from Nandamūlaka-pabbhāra.

Xuanzang quotes the Nigrodhamiga Jātaka to account for the origin of the Migadāya. According to him the Deer Park was a forest given by the king of Benares of the Jātaka, where deer might wander unmolested. The Migadāya was so-called because deer were allowed to roam about there unmolested.

Sarnath derives from the Sanskrit Sāranganātha, which means "Lord of the Deer", and relates to another old Buddhist story in which the Bodhisattva is a deer and offers his life to a king instead of the doe the latter is planning to kill. The king is so moved that he creates the park as a sanctuary for deer. The park is active in modern times.

Before Gautama (the Buddha-to-be) attained enlightenment, he gave up his austere penances and his friends, the Pañcavaggiya monks. Seven weeks after his enlightenment under the Bodhi tree in Bodh Gaya, Buddha left Uruvela and travelled to Isipatana to rejoin them because, using his spiritual powers, he had seen that his five former companions would be able to understand Dharma quickly. While traveling to Sarnath, Gautama Buddha had no money to pay the ferryman to cross the Ganges, so he crossed it through the air.[citation needed] Later when King Bimbisāra heard of this, he abolished the toll for ascetics. Gautama Buddha found his five former companions and enlightened them with the teachings of the Dharma. At that time, the Sangha, the community of the enlightened ones, was founded. The sermon, Buddha gave to the five monks, was his first sermon, called the Dhammacakkappavattana Sutta. It was given on the full-moon day of Asalha Puja. Buddha subsequently also spent his first rainy season at Sarnath at the Mulagandhakuti. By then, the Sangha had grown to 60 in number (after Yasa and his friends had become monks), and so Buddha sent them out in all directions to travel alone and teach the Dharma. All 60 monks were Arhats.

Several other incidents connected with the Buddha, besides the preaching of the first sermon, are mentioned as having taken place in Isipatana. It was here when one day, at dawn, Yasa came to the Buddha and became an Arhat. It was at Isipatana, too, that the rule was passed, prohibiting the use of sandals made of talipot leaves. On another occasion when the Buddha was staying at Isipatana, having gone there from Rājagaha, he instituted rules forbidding the use of certain kinds of flesh, including human flesh. Twice, while the Buddha was at Isipatana, Māra visited him but had to go away discomfited.