Minneriya and Kaudulla National Parks lie in the Mahaweli region of north-central Sri Lanka. Minneriya was designated as a National Park in 1997 and Kaudulla in 2002 to help to establish habitat connectivity for elephants that are believed to move between Minneriya in the south, Hurulu Biosphere Reserve in the west, Kaudulla in the north and Somawathiya Chaitya National Park further north and east.
The two national parks are small, Minneriya composed of 8,889 Ha and Kaudulla 6,900 Ha, and separated by eight km. Both national parks encompass large reservoirs, or tanks, at which several hundred elephants congregate during the dry season to feed on grass exposed by the receding waters. Kaudulla and Minneriya National Parks consist of tank-edge grasslands and dry mixed evergreen forest. The Yoda Ela river flows through Kaudulla National Park lined by beautiful riverine forest.
The history of Minneriya and Kaudulla can be traced back some 1700 years to the reign of King Mahasen. The tanks were built with the help of captive elephants between A.D. 274-301. You can read some more about the construction of these tanks on Wiki.