M4 corridor bridge, serving Chepstow, being renumbered the M48, although the area is still generally considered as falling within the M4 corridor. Since the start of the 21st Century there has been evidence of more investment west of Cardiff, such as: M4 corridor The M4 corridor is an area in the United Kingdom adjacent to the M4 motorway, which runs from London to South Wales. It is a major high-technology hub. Important cities and towns linked by the M4 include (from east to west) London, Slough, Bracknell, Maidenhead, Reading, Newbury, Swindon, Bath, Bristol, Newport, Cardiff, and Swansea. The area is also served
M4 Western Motorway entire motorway was allocated the M4 route. The non-motorway section of Metroad 4 was however replaced by A4. The eastern end of the M4 is currently at North Strathfield, some from the Sydney central business district. Over the years a number of proposals have been made to extend the M4 east towards the city. One plan in the 1990s involved extending the M4 eastwards by approximately so that it would subsequently end in Ashfield and be continuous with the City West Link. Further planned upgrades to the City West Link would mean commuters going west out of the city could