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 Tractor of which are still in service. The original Finning Tank Drill was replaced by the M32F and M40F Tank Drills, which used larger Sherman tank carriers. At Amsterdam Airport Schiphol in the Netherlands, at least two refurbished M4s were used by the airport fire brigade in the 1960s and '70s. M4 Tractor The M4 High-Speed Tractor was an artillery tractor used by the US Army from 1943. The M4 was based on the chassis and drive train of the obsolescent M3 Light Tank which introduced the trailing idler. One variant was designed to tow the 3-inch or 90 mm anti-aircraft