The National Fossil Wood Park, Tiruvakkarai is a notified National Geo-heritage Monument located in the Villupuram District in the Indian state of Tamil Nadu and is maintained by the Geological Survey of India. The park was established in 1940 and is located 1 km east of Thiruvakkarai village on the road between Tindivanam and Pondicherry. The park contains petrified wood fossils approximately 20 million years old, scattered throughout the park, which covers about 247 acres (100 ha). The park consists of nine enclaves, but only a small portion of the 247 acres (approx 1 square km) is open to the public. Officials of the GSI believe the fossils were formed during massive flooding that occurred millions of years ago. The park hosts about 200 fossilized trees. They range in size from 3 to 15 metres (9.8 to 49.2 ft) meters in length, some of which are up to 5 meters in width. They are strewn and partially buried in the park grounds. No branches or leaves remain on the fossilised trunks.