M25 users should note that from early January 2004 the motorway is again being widened, this time between junction 12 (M3 interchange) and junction 15 (M4). The work will last two years and will be carried out in two sections, firstly between J12 and J14, and fully up to J15. At the same time the Heathrow T5 spur road will be built. Currently over 200,000 vehicles per day use this section of motorway which will be increased to 240,000 once the widening is complete. It is thought to be the busiest section of roadway in Europe. http://www.highways.gov.uk