The Kamakhya Temple at Nilachal hills in Guwahati, Assam is one of the oldest and most revered centres of Tantric practices, dedicated to the goddess Kamakhya. The temple is the center of the Kulachara Tantra Marga and the site of the Ambubachi Mela, an annual festival that celebrates the menstruation of the goddess. Structurally, the temple is dated to the 8th-9th century with many subsequent rebuildings—and the final hybrid architecture defines a local style called Nilachal. It is also one among the oldest 4 of the 51 pithas in the Shakta tradition. An obscure place of worship for much of history it became an important pilgrimage destination, especially for those from Bengal, in the 19th century during colonial rule.
Originally an autochthonous place of worship of a local goddess where the primary worship of the aniconic yoni set in natural stone continues till today, the Kamakya Temple became identified with the state power when the Mleccha dynasty of Kamarupa patronised it first, followed by the Palas, the Koch, and the Ahoms. The Kalika Purana, written during the Pala rule, connected Naraka, the legitimizing progenitor of the Kamarupa kings, with the goddess Kamakhya representing the region and the Kamarupa kingdom.
It has been suggested that historically the worship progressed in three phases—yoni under the Mlechhas, yogini under the Palas and the Mahavidyas under the Kochs. The main temple is surrounded in a complex of individual temples dedicated to the ten Mahavidyas of Saktism, namely, Kali, Tara, Tripura Sundari, Bhuvaneshwari, Bhairavi, Chhinnamasta, Dhumavati, Bagalamukhi, Matangi and Kamalatmika. Among these, Tripurasundari, Matangi and Kamala reside inside the main temple whereas the other seven reside in individual temples. Temples for individual Mahavidyas together as a group, as found in the complex, is rare and uncommon.
In July 2015, the Supreme Court of India transferred the administration of the Temple from the Kamakhya Debutter Board to the Bordeuri Samaj.