From Wikipedia, the free encyclopedia

The M4 corridor is the area adjacent to the M4 motorway. Its eastern end in particular is home to a large number of businesses, particularly in Berkshire, Swindon and the Thames Valley. For this reason this part of the M4 Corridor is sometimes described as the United Kingdom's Silicon Valley. Often the term 'M4 Corridor' is used to denote only the far Eastern part roughly from Swindon to London.

Companies which have offices along the M4 include Vodafone, Cisco, Microsoft, Hewlett Packard, and MCI. As with many motorways, companies are attracted to the location because of the ease of travel, this is true of the M4 especially because of the motorway's proximity to London and Heathrow Airport which is also alongside the M4.

Investment has gradually spread westwards since the 1980s. Further west the interchange of the M4 motorway and M5 motorway near Bristol had seen considerable growth of industries by the mid 1990s, where, for example, the headquarters of Orange is located. Indeed by the end of the 1990s there were even signs of investment into South Wales, whose economy had suffered badly during the 1980s. The Celtic Manor Resort located adjacent to the M4 in Newport has undergone significant investment and will host the 2010 Ryder Cup. Newport is home to factories for many electronics firms, such as Panasonic and Alcatel. The 1990s also saw significant investment in Cardiff such as in Cardiff Gate and the Cardiff Bay area.

Since the start of the 21st Century there has been some evidence of investment west of Cardiff, such as the SA1 development in Swansea.

Despite recent development the M4 corridor still has within it some of the poorest areas in Western Europe as well as the wealthiest.

Apart from London which is at the end of the M4 motorway, Staines, Slough, Windsor, Maidenhead, Reading, and Newbury are the main towns in the Berkshire stretch of the M4 (although Staines is in Surrey), and this area, plus the nearby borough of Swindon, forms the most popular location for businesses in the M4 corridor. Reading is home to many of the businesses (such as Microsoft, Ericsson managing services for Hutchison 3G and MCI) whilst Vodafone is located in Newbury, O2 plc is in Slough and headquarters of Hutchison 3G UK are in Maidenhead. The M4 also passes the cities of Bath and Bristol before continuing into South Wales and the cities of Newport, Cardiff and Swansea.

The M4/M25 junction is large and impressive, one of only three four-level stack interchanges in the UK's motorway network.^{[citation needed]}