Broad-gauge railway in the context of "Narrow-gauge railway"

An elevated railway or elevated train (also known as an el train or el for short) is a railway with the tracks above street level on a viaduct or other elevated structure (usually constructed from steel, cast iron, concrete, or bricks). The railway may be a broad-gauge, standard-gauge or narrow-gauge railway, rapid transit, light rail, monorail, or a suspension railway. Elevated railways are normally found in urban areas that would otherwise require impracticably many level crossings. Usually, the tracks of elevated railways that run on steel viaducts can be seen from street level.

Mettupalayam railway station (station code: MTP) is an NSG–4 category Indian railway station in Salem railway division of Southern Railway zone. It is a railway station located in Mettupalayam, a suburb of Coimbatore district in the Indian state Tamil Nadu. It is one of the important railway stations located in the Coimbatore District, because the Nilgiri Mountain Railway to the hill station of Ooty starts from here. It is the connection between the metre-gauge Nilgiri Mountain Railway and the broad-gauge main network of Indian Railways. It recently celebrated its 150th anniversary.

The Grand Trunk Express operated from Mettupalayam to Peshawar from 15 October 1929 and was extended to Lahore from 1 March 1930. Later that year, on 1 September 1930, it was changed to New Delhi to Chennai, which remains the case till today. The Tea Garden Express ran in metre gauge between Ooty and Mettupalayam and broad gauge between Mettupalayam and Cochin Harbour Terminus. Post-Indian independence, the Ooty–Mettupalayam trip was cut off, and the train ran as No. 565/566 between Cochin Harbour Terminus and Mettupalayam since the 1970s. Today the Nilgiri Express (also known as the Blue Mountain Express) covers Chennai to Mettupalayam and acts as the link to Ooty. Nilgiri Express used to be the main portion of Bangalore Mail, Island Express, Malabar Express and Mumbai–Coimbatore (through coach bifurcate/amalgamate to Chennai–Mumbai Mail).

Iberian gauge (Spanish: ancho ibérico, trocha ibérica, Portuguese: bitola ibérica) is a track gauge of 1,668 mm (5 ft 5+21⁄32 in), most extensively used by the railways of Spain and Portugal. A broad gauge, it is the second-widest gauge in regular use anywhere in the world, with only Indian gauge railways, 5 ft 6 in (1,676 mm), being wider (by 8 mm (5⁄16 in)).

As finally established in 1955, the Iberian gauge is a compromise between the similar, but slightly different, gauges adopted as respective national standards in Spain and Portugal in the mid-19th century. The main railway networks of Spain were initially constructed to a 1,672 mm (5 ft 5+13⁄16 in) gauge of six Castilian feet. Those of Portugal were instead built to a 1,435 mm (4 ft 8+1⁄2 in) and later railways to a 1,664 mm (5 ft 5+1⁄2 in) gauge of five Portuguese feet – close enough to allow interoperability with Spanish railways.