Geocenter produce clear and readable street mapping for most of the world's main cities. Where possible each map will cover most of the city, however with large cities like New York or London, this is reduced to just the central areas. Main thoroughfares are marked in yellow and one-way streets are usually clearly indicated with an arrow showing the direction of traffic. Important buildings are highlighted. Bus, tram and metro routes, where applicable are either overlaid on the main map or detailed in insets. All maps are indexed on the reverse.