An island platform (also center platform, centre platform) is a station layout arrangement where a single platform is positioned between two tracks within a railway station, tram stop or transitway interchange. Island platforms are popular on twin-track routes and can provide for services in both directions from a single platform requiring only one set of supporting services (lifts, escalators, toilets, ticket offices, kiosks). They are also useful within larger stations where local and express services for the same direction of travel can be provided from opposite sides of the same platform thereby simplifying transfers between the two. An alternative arrangement is to position side platforms on either side of the tracks.