Historic Jaffna Fort, situated on the south of the Jaffna peninsula at the water’s edge of the lagoon is the second largest existing historic Fort in the country.

This was originally built by the Portuguese in 1619 and later during the second half of the 17th and the 18th centuries Dutch who invaded the island after Portuguese re-built and expanded to facilitate their commerce.

This was fortified thick and high ramparts and a wide and deep moat around it. The layout resembles a geometrically regular pentagon, which is defined by the ramparts with a bastion at each corner of the pentagon. Beyond these defense works is the star-shaped moat, the outline of which roughly follows the bastion and rampart walls.

Unlike the Dutch forts at Galle and Colombo, which were fortified towns, the Jaffna Fort had an almost exclusively military and administrative function. The fort is the only surviving example in Sri Lanka, where its inner defenses has a geometrically regular pentagonal layout.