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
M25 motorway motorways. The M25 is the second-longest ring road in Europe, after the Berlin Ring (A 10), which is longer. Other cities in the UK encircled by motorways include: Birmingham, using parts of the M5, M6 and M42, and Manchester, using the M60. Additionally, from 2011 Glasgow has an orbital motorway made of the M8, M73 and M74, although one section of the route passes through the centre of the city. The M25 is one of the busiest motorways in Europe. Here are some comparisons: Iain Sinclair's 2002 book and film "London Orbital" is based on a year-long journey around the