Pichavaram (Tamil: பிச்சாவரம்) is located near Chidambaram in Cuddalore District, Tamil Nadu, in South India. The nearest railway station is Chidambaram from where it is accessible by road. The Pichavaram Mangrove Forest near Chidambaram, South India, by the Bay of Bengal is the world's second largest mangrove forest.Pichavaram mangrove forest is located between two prominent estuaries, the Vellar estuary in the north and Coleroon estuary in the south. The Vellar - Coleroon estuarine complex forms the Killai backwater and Pichavaram mangroves.The backwaters, interconnected by the Vellar and Coleroon river systems, offer abundant scope for water sports such as rowing, kayaking and canoeing. The Pichavaram forest not only offers waterscape and backwater cruises, but also another very rare sight - the mangrove forest trees are permanently rooted in a few feet of water. There are more than 400 water routes available for boating.