The district has an area of 2,552.50 km².
The district is basically hilly, lying at an elevation of 1,000 to 2,600 metres above MSL, and divided between the Nilgiri plateau and the lower, smaller Wayanad plateau.
The district lies at the juncture of the Western Ghats and the Eastern Ghats.
Its latitudinal and longitudinal location is 130 km (Latitude: 11°12 N to 11°37 N) by 185 km (Longitude : 76°30 E to 76°55 E).
The district is bounded by Coimbatore to the south, Erode to the east, Chamarajnagar district of Karnataka to the north, and Wayanad, Malappuram and Palakkad districts of Kerala to the east.
In this district the topography is rolling, with steep escarpments; about 60% of the cultivable land is slopes ranging from 16° to 35°.
The rolling hills of the Downs look quite similar to the Downs in southern England, and were formerly used for such activities as hunting and picnicking.

The elevation of the Nilgiris results in a much cooler and wetter climate than the surrounding plains, so the area is popular as a comfortable retreat and is good for tea cultivation.
During summer the temperature reaches a maximum of 25 °C (77 °F) and a minimum of 10 °C (50 °F).
During winter the temperature maximum is 20 °C (68 °F) and the minimum 0 °C (32 °F).
The district regularly receives rain during both the Southwest Monsoon and the Northeast Monsoon.
The entire Gudalur and Pandalur, Kundah Taluks and parts of Udhagamandalam Taluk get rain from the Southwest Monsoon, while part of Udhagamandalam Taluk and the entire Coonoor and Kotagiri Taluks get rains of the Northeast Monsoon.
There are 16 rainfall-registering stations in the district, and the average annual rainfall of the district is 1,920.80 mm.

The principal town of the area is Ootacamund, also known as Ooty or Udhagamandalam, the district headquarters.
It has several buildings designed in the British style, particularly the churches, many of which were designed by architect Robert F. Chisholm.
A road junction became known as Charing Cross (after famous intersections in London and Lahore).
The other main towns in the Nilgiris are Coonoor, Kotagiri, Gudalur and Wellington.
Several tourist spots in Coonoor include Lambs Rock and Sims Park, where a Fruit Show is held during each summer.
Ooty too has an annual summer flower show.
The district has an area of 2,552.50 km². The district is basically hilly, lying at an elevation of 1,000 to 2,600 metres above MSL, and divided between the Nilgiri plateau and the lower, smaller Wayanad plateau. The district lies at the juncture of the Western Ghats and the Eastern Ghats. Its latitudinal and longitudinal location is 130 km (Latitude: 11°12 N to 11°37 N) by 185 km (Longitude : 76°30 E to 76°55 E). The district is bounded by Coimbatore to the south, Erode to the east, Chamarajnagar district of Karnataka to the north, and Wayanad, Malappuram and Palakkad districts of Kerala to the east. In this district the topography is rolling, with steep escarpments; about 60% of the cultivable land is slopes ranging from 16° to 35°. The rolling hills of the Downs look quite similar to the Downs in southern England, and were formerly used for such activities as hunting and picnicking.
The elevation of the Nilgiris results in a much cooler and wetter climate than the surrounding plains, so the area is popular as a comfortable retreat and is good for tea cultivation. During summer the temperature reaches a maximum of 25 °C (77 °F) and a minimum of 10 °C (50 °F). During winter the temperature maximum is 20 °C (68 °F) and the minimum 0 °C (32 °F). The district regularly receives rain during both the Southwest Monsoon and the Northeast Monsoon. The entire Gudalur and Pandalur, Kundah Taluks and parts of Udhagamandalam Taluk get rain from the Southwest Monsoon, while part of Udhagamandalam Taluk and the entire Coonoor and Kotagiri Taluks get rains of the Northeast Monsoon. There are 16 rainfall-registering stations in the district, and the average annual rainfall of the district is 1,920.80 mm.
The principal town of the area is Ootacamund, also known as Ooty or Udhagamandalam, the district headquarters. It has several buildings designed in the British style, particularly the churches, many of which were designed by architect Robert F. Chisholm. A road junction became known as Charing Cross (after famous intersections in London and Lahore). The other main towns in the Nilgiris are Coonoor, Kotagiri, Gudalur and Wellington. Several tourist spots in Coonoor include Lambs Rock and Sims Park, where a Fruit Show is held during each summer. Ooty too has an annual summer flower show.
Nilgiris district