Vattakottai Fort (Circular Fort) is a seaside fort built in 18th century. It was constructed under the command of Captain Eustachius De Lannoy during the reign of Travancore King Marthandavarma (1729-58) in the 18th century. It is a symbol of the military history of India

Vattakottai Fort is about 7 km from Kanyakumari. It covers an area of about three and a half acres. The fort is enclosed by walls 25 to 26 feet high, including the parapet, 29 feet thick at the front, 18 feet at the corners and 6 feet at the rear.

The fort is made of granite blocks and it is a protected site under the Indian archaeological department. A major renovation of the fort was undertaken recently by the department, and the site is now a popular tourist spot.