Elevated railway

Rapid transit railway with the tracks above street level

An elevated railway or elevated train (also known as an el train or el for short, and sometimes also spelled as L train) 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.

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