The 46 km Nilgiri Mountain Railway Climbs 1,877 Metres and Needs a Toothed Rail for Its Steepest Stretch

The Nilgiri Mountain Railway runs 46 km from Mettupalayam, at 326 metres above sea level, to Udhagamandalam, the hill town most people call Ooty, at 2,203 metres. That is a rise of 1,877 metres on a single track whose rails are one metre apart, and the regular morning train takes about five hours to do it.

On the steepest stretch a toothed rail laid between the running rails meshes with a cog wheel under the engine. This is called a rack and pinion. An Indian Steam Railway Society article hosted by the Indian Railways Fan Club calls it the only metre-gauge mountain line in India worked that way, and UNESCO added it to the Mountain Railways of India World Heritage listing in 2005.

From a proposal in 1854 to a first sod in 1891

UNESCO’s description of the site says the line was first proposed in 1854 and that the mountainous ground delayed work until 1891. A 1908 account of the line, reproduced by the Indian Railways Fan Club, fills in the years between. In 1876 the Swiss engineer Riggenbach offered to build a line on the Rigi rack pattern, and the government declined. In 1880 he and Major Morant, the district engineer, costed a rack railway.

The Nilgiri Railway Company was registered on 30 September 1885, according to the FIBIS records. Lord Wenlock, Governor of Madras, cut the first sod in August 1891. The company went into liquidation in April 1894, and in February 1896 a new one took over, with free land and a government guarantee of a 3% return on its capital during construction. That is a smaller version of the guarantee described in our piece on who paid for India’s railways.

Why a hill railway needs a toothed rail

The 1908 account gives the line’s ruling gradient as 1 in 12½, meaning a rise of one metre for every 12.5 metres of track, starting at Kallar, five miles out of Mettupalayam. The Heritage Directorate of Indian Railways says an ordinary railway relies on wheel grip alone up to about 1 in 14.5, so the steeper sections needed something extra.

The system chosen was the Abt rack, which the 1908 account calls an improved modification of the Rigi principle. An Indian Steam Railway Society article puts the average gradient on the rack section at 1 in 12.28, and an account of the X class locomotives gives the rack’s length as 20 km, from Kallar to Coonoor. The Heritage Directorate says the train climbs at about 13 km/h.

The route has 16 tunnels, and the Heritage Directorate counts more than 250 bridges. Other published counts differ: Onmanorama’s 2025 guide gives 206 bridges. A Google Arts & Culture story on the line’s stations says building it meant cutting through solid granite, and the Heritage Directorate notes that many tunnels are unlined hard rock.

Coonoor in 1899, Ooty in 1908

The first section, 27 km from Mettupalayam to Coonoor, opened on 15 June 1899, with the Madras Railway working it under an agreement. The Fan Club’s society article says the line was meant to carry officials up to Ootacamund (the British spelling of Ooty) and to move the Nilgiris’ tea to ports on the west coast.

The returns were thin. The government bought the line on 1 January 1903 for 35 lakh rupees (£235,000, per FIBIS), after 48 lakh had been spent. The 1908 account records that net earnings were paying just over 2% interest on the purchase price, and that landslips made upkeep costly.

The 19 km extension from Coonoor to Ooty has no rack. Its steepest gradient is 1 in 25, according to the 1908 account, which estimated the cost at Rs 24,40,000 and says the 61st and 64th Pioneers, army regiments, did much of the earthwork under contract. FIBIS names R. R. Gales as the Public Works Department’s engineer-in-chief. The Heritage Directorate says the line reached Ootacamund in 1908, and UNESCO gives 1908 as the year of completion.

So both 1899 and 1908 are correct for different stretches. UNESCO’s text says the railway “represented the latest technology of the time.”

The Swiss engines and what runs today

The steam engines on the rack are the X class. The Indian Steam Railway Society account says the Swiss Locomotive and Machine Works of Winterthur built 12 of them in two lots, seven that entered service in 1920 to 1925 and five in 1952, all based at the Coonoor shed when the article was written. They are compound locomotives with four cylinders: the high-pressure pair drives the ordinary wheels, and the low-pressure pair above it drives the cog wheels that grip the rack.

Dates for the oldest engines are not settled. The National Rail Museum says X-37385 was imported from Switzerland in 1921 and weighs 48.9 tonnes. The Deccan Chronicle reported in 2019 that No. 37384 was built in Switzerland in 1914 and entered service on the line in 1918.

Coal was the original fuel. The society article says one engine was converted to burn furnace oil during 2002 and 2003, and the Heritage Directorate says most of the Swiss-built engines have since been converted, with four new oil-fired engines built at the Golden Rock workshop in Tiruchirappalli. RailPost reported that Golden Rock built a coal-fired X class, No. X-37400, which Southern Railway’s general manager John Thomas flagged off on 25 August 2021. It is 10.38 metres long and weighs 50 tonnes.

The Heritage Directorate says only specially fitted steam engines can work the rack, and FIBIS says diesels can haul trains only between Coonoor and Ooty. The National Rail Museum’s account of a Nilgiri coach built in 1919 says the coaches still use hand-applied mechanical brakes, with one brake man for each coach.

How the line got on the UNESCO list

A Press Information Bureau document on India’s UNESCO sites, posted in July 2024, lists the Mountain Railways of India with inscription years of 1999, 2005 and 2008. The Darjeeling Himalayan Railway came first in 1999. The Nilgiri line was added in 2005, and the Kalka Shimla Railway in 2008.

UNESCO’s news release of 15 July 2005 says the World Heritage Committee, meeting in Durban, South Africa, extended six existing sites that day, among them the Mountain Railways of India. The Press Information Bureau document adds that all three railways are still fully operational.

Trains and timings in 2026

Southern Railway runs about eight regular trips a day, according to Curly Tales’ report of the February 2026 fare revision. DT Next reported on 8 March 2026 that the regular train normally leaves Mettupalayam at 7:10 am and reaches Ooty around noon. An undated page from the Heritage Directorate says just one train runs each way on the rack section between Mettupalayam and Coonoor, timed to connect with the Nilgiri Express from Chennai.

A summer special also ran in 2026, per DT Next, from 27 March to 5 July. The Mettupalayam to Ooty train ran on Fridays and Sundays, leaving at 9:10 am and arriving at 2:25 pm. The return ran on Saturdays and Mondays, leaving Ooty at 11:25 am and arriving at 4:20 pm. Officials said many passengers had been unable to get tickets because of heavy demand. The special has ended for this year, and whether it returns in 2027 is for Southern Railway to announce.

Reports disagree on what hauls a normal day’s train. The Heritage Directorate describes steam on the rack, while The News Minute reported in December 2019 that the line normally ran on diesel and used steam only rarely. We could not open a current official statement, so ask Southern Railway if steam matters to you. The station codes to use when searching are UAM for Ooty and ONR for Coonoor.

Fares, booking and cancellations

We checked the practical details below on 8 October 2026 against news reports of Southern Railway announcements. Southern Railway’s own pages and IRCTC’s booking page would not load for us, so confirm with both before you travel.

Southern Railway raised base fares on regular trains by 5% from Saturday, 21 February 2026, Curly Tales reported. Special trains and charter services were not covered, and reservation charges were unchanged. The report says regular fares had not changed since 18 February 2020, and that haulage charges between Mettupalayam and Coonoor had risen by more than 200%. Curly Tales quotes second-class fares of Rs 200 for Mettupalayam to Coonoor and Rs 160 for Coonoor to Ooty. We could not find an official fare table, so treat these as indicative and check the fare shown when you book.

Onmanorama’s 2025 guide says tickets can be bought on the Indian Railways website or at the station where you board, and advises reaching the counter an hour early. Since 1 November 2024 Indian Railways has limited advance reservations to 60 days before the travel date, with exceptions for a few daytime expresses and for foreign tourists, who keep 365 days. Whether a given Nilgiri train follows the general rule is shown on the booking page.

Weather cancels trains. On 2 January 2026 the Salem division cancelled all services between Coonoor and Udhagamandalam after landslips, and Coonoor recorded 215 mm of rain that day, Onmanorama reported.