The topography of Tamil Nadu varies dramatically from east to west. The eastern coastline features broad, flat plains and river deltas that are prone to flooding and are intensely cultivated. Moving inland, the terrain gradually rises into undulating plateaus.
The western border is defined by the towering Western Ghats, a UNESCO World Heritage biodiversity hotspot. Here lies the state's highest point, Doddabetta Peak, which reaches an elevation of 2,637 meters (8,652 feet) in the Nilgiri Hills. The Eastern Ghats are more fragmented and discontinuous, intersecting with the Western Ghats at the Nilgiris. The lowest point is at sea level along the 1,076 km (668 mi) coastline bordering the Bay of Bengal and the Gulf of Mannar.