Thondaimanaru Lagoon

Thondaimanaru Lagoon stretches along the northern edge of the Vadamarachchi peninsula, separated from the open sea by a long sandbar and controlled by a colonial-era barrage that regulates the salinity of the water. The lagoon is large but shallow, brackish rather than fully saline, and ringed by mangrove on the inland side and palmyra further back.

The barrage at the western end is the structural feature that defines the place. It was originally built in the British period to manage the exchange of seawater into the lagoon, and it still functions today — opened and closed seasonally to balance the lagoon's ecology with the demands of the surrounding rice paddies and prawn farms. The villages along the lagoon are quietly working ones: prawn aquaculture is a significant local industry, and the wooden walkways and shallow ponds that hold the farms are visible from the road in places.

The lagoon is most rewarding in the early hour after sunrise. Egrets, herons, kingfishers, and a range of waders work the mudflats; cormorants dry their wings on the prawn-farm posts; and on quieter mornings flocks of duck and tern lift off the open water. It is not as known a birding site as Jaffna Lagoon or Chundikulam, which is part of its appeal — there are no boardwalks, no organised hides, just the road along the southern shore and the quiet to listen.

Visitors who come here usually combine it with the Manalkadu Dutch Church, Manalkadu Beach, and the Point Pedro lighthouse on a longer day along the eastern coast. There are no formal facilities; bring water, binoculars if you have them, and respect for the working livelihoods along the shore.