The use of geographic numbers may also lead to tromboning; one can take a handset with a Vancouver number into St. John's and outbound calls to St. John's numbers while in that city will be local, but incoming calls must make the cross-country trip to Vancouver and back. This adds costs for subscribers, as an 8,000 km cross-country call (as a worst case) incurs long-distance tolls in both directions. AMPS subscribers used to be provided with a local number (such as 1-NPA-NXX-ROAM) in each city, allowing them to be reached by dialing that number plus the ten-digit mobile telephone number; this is no longer supported.