An elevated railway (also known in Europe as overhead railway) is a rapid transit railway with the tracks above street level on a viaduct or other steel, concrete or brick structure. The railway may be standard gauge, narrow gauge, light rail, monorail or a suspension railway. Elevated railways are usually used in urban areas where there would otherwise be a large number of level crossings. Most of the time, the tracks of elevated railways that run on steel viaducts can be seen from street level.

Rapid transit, also known as metro, subway or underground is a type of high-capacity public transport generally found in urban areas. Unlike buses or trams, rapid transit systems are electric railways that operate on an exclusive right-of-way, which cannot be accessed by pedestrians or other vehicles of any sort, and which is often grade separated in tunnels or on elevated railways.