The Nilgiris District is in the southern Indian state of Tamil Nadu. Nilgiri is the name given to a range of mountains spread across the borders among the states of Tamil Nadu, Karnataka and Kerala. The Nilgiri Hills are part of a larger mountain chain known as the Western Ghats. Their highest point is the mountain of Doddabetta, height 2,633 m. The small district is contained mainly within this mountain range; the administrative headquarters is located at Ooty. Tourism is an important source of revenue for the Nilgiris.The district is home to several beautiful hill stations popular with tourists who flock to them during summer. These include Udhagamandalam, Coonoor, Gudalur and Kotagiri. The Nilgiri Mountain Train, popularly known as the Toy Train, attracts tourists as the journey offers spectacular, breathtaking views of the hills and forests. Mudumalai National Park is popular with wildlife.