Railway Tracks
Railroad or railway tracks are used on railways, which, together with railroad switches, guide trains without navigation. They consist of two parallel steel rails, which are laid and fastened upon sleepers which are fixed in ballast to form the railroad track. Rail tracks are normally laid on a bed of coarse stone chippings known as ballast, which combines flexibility, some amount of elasticity, and good drainage; however, track can also be laid on or into concrete (across bridges, for example).