Urmia Lake is a salt lake in northwestern Iran near Turkey. The lake is between the provinces of East Azerbaijan and West Azerbaijan, west of the southern portion of the similarly shaped Caspian Sea. It is the largest lake inside Middle East, and the third largest salt water lake on earth, with a surface area of approximately 5,200 km² (2,000 mile²). At its maximum extent, it is about 140 km (87 miles) long, and 55 km (34 miles) wide. Its deepest point is approximately 16 m (52 ft) deep.