Roads also cover streets, bridges, tunnels, supporting structures, junctions, crossings and interchanges. The city is served by two full interchanges and one partial interchange. Toll plazas are located at each of those interchanges. All three unbuilt interchanges incorporate interchanges with local roads. There are four major components of public transport, with many intermodal interchanges. The metropolis of Tehran is equipped with a large network of highways and interchanges. There are two interchanges with Highway 401 on Kitchener's southern border. Central and Circular Quay are transport hubs with ferry, rail, and bus interchanges. The highway is also extra high to allow for possible multiple interchanges. It is accessible from the two highway interchanges of Palladium Drive and Terry Fox Drive. The same applies to names of the motorway interchanges and rest areas. Step-free routes are available between the Victoria line and other lines at most interchanges. These interchanges back up traffic and causes gridlock. Construction of four sound barriers between the US 1 and I-95 interchanges were also included. Heading south, MD 17 interchanges with U.S. Route 340 just before reaching Brunswick.