M25 motorway re-examined as a motorway route in Sir Charles Bressey's and Sir Edwin Lutyens' "The Highway Development Survey, 1937". Sir Patrick Abercrombie's "County of London Plan, 1943" and "Greater London Plan, 1944" proposed a series of five roads encircling the capital. The northern sections of the M25 follow a similar route to the World War II Outer London Defence Ring, a concentric series of tanks and pillboxes designed to slow down a potential German invasion of the capital. Little was done to progress these plans until the 1960s when the Greater London Council developed its London Ringways plan consisting of four
London the outer orbital motorway (the M25, outside the built-up area) encircle the city and are intersected by a number of busy radial routes—but very few motorways penetrate into inner London. A plan for a comprehensive network of motorways throughout the city (the Ringways Plan) was prepared in the 1960s but was mostly cancelled in the early 1970s. The M25 is the second-longest ring-road motorway in Europe at long. The A1 and M1 connect London to Leeds, and Newcastle and Edinburgh. London is notorious for its traffic congestion, with the average speed of a car in the rush hour being .