Sarnath, Varanasi is known for two things: Buddha gave his first sermon and for the Ashoka Pillar.
In ancient times, this place was known by many names — Rishipatana, Mrigadava and Mrigadaya. The word Sarnath comes from a corruption of the name Saranganatha (lord of deer).
The ashes of the Buddha were buried in stupas built at locations associated with important events in the Buddha’s life including:
Lumbini (where he was born), Bodh Gaya (where he achieved Enlightenment), Deer Park at Sarnath (where he preached his first sermon sharing the Four Noble Truths (also called the dharma or the law), and Kushinagara (where he died).
The choice of these sites and others were based on both real and legendary events.
Stupas at Sarnath

Two hundred years after Buddha, the Mauryan emperor, Ashoka, fought the battle of Kalinga and, disgusted by the bloodshed, became a Buddhist.
Ashoka built many beautiful stupas and monasteries in Sarnath.
Sir Alexander Cunningham (First Director-General of Archaeological Survey of India), excavated the Dhamekh, Dharmarajika, and Chaukhandi stupas along with a monastery and temple between 1834 and 1836.