Adayar is a locality on the sea shore of Chennai (previously Madras), one of the four metropolitan cities of India. Chennai is a port of the Bay of Bengal and is one of the important places where the British Colonization started in India.

Adayar is famous for the Theosophical Society around which the locality is centered. It is also famous for the Beach nearby which is a tourist attraction. The Tidel Park, an IT park is also situated at Adyar. Adyar has recently gained prominence in Chennai due to its proximity to the rapidly growing IT centres along the East Coast Road and due to the mushrooming of a large number of educational institutions along the road.