Ousteri lake, often seen on maps as Osudu lake is a large freshwater lake in Puducherry. Spread over 390 hectares, this man-made lake is shared between Tamil Nadu and the union territory of Puducherry. For a day away from the buzzing city and crowd, this isolated lake just offers the visitors the right amount of solitude. It is located at a distance of 10 kms from the Puducherry city center.

The scenic location of the Ousteri lake is famous for hosting a wide range of migratory birds. The tourism department has recorded more than 40 migratory birds that visit the Ousteri lake all throughout the year. Ousteri lake is recognized as one of the important wetlands of Asia by IUCN (the International Union for Conservation of Nature and Natural resources). As the lake is little out of the way in regular travel agenda, it remains little explored by the tourist folk.

Some of the spectacular migratory species that are spotted in the lake include Golden Oriole, Painted Stork, White Ibis, Open-bill Stork, White-breasted water-hen and spotted owlets. These winged visitors usually make a visit after November every year. However, it is also a home to many native birds in winters and as well as in summers. Apart from a 15-30 minutes boat ride that attracts the tourist circuit, it provides an amazing scenary to the visitors. The best time to visit Ousteri lake is from October to March. Visitors usually spend about an hour or two at the Ousteri lake.

Visitors can visit Ousteri lake during timings 9:00 AM - 5:00 PM. There is no entry fee as such, but the boat rides, camera, snacks, and beverages are to be paid for. Also, note that each boat ride would require a minimum headcount. But they also have kayaks and peddle boats which would require a minimum of 2-5 people.