M25 motorway

The M25 motorway is a major ring road that encircles most of Greater London. It stretches for 117 miles and is one of the busiest roads in the UK. Margaret Thatcher opened the final section in 1986, making it the longest ring road in Europe at the time. The motorway is not a continuous route; the Dartford Crossing completes the loop but is a trunk road rather than motorway. In legal contexts, the M25 often serves as a boundary for Greater London. The road was first proposed in the 1944 Greater London Plan by Patrick Abercrombie. The M25 evolved from the London Ringways project in the 1960s, which planned two separate routes. By 1966, these were combined into a single orbital motorway. Environmental concerns led to nearly 40 public inquiries during its construction. Some sections, like the one over the North Downs and around Epping Forest, required extensions such as the Bell Common Tunnel. Despite initial popularity, the motorway soon faced congestion issues due to insufficient capacity. The motorway passes through several counties, including Hertfordshire between junctions 17 and 24. It runs close to landmarks such as Chevening, Titsey Place, Hever Castle and Chartwell. The interchange with the M23 near Reigate is a rare four-level stack. The northern section passes near All Saints Pastoral Centre, Waltham Abbey and Copped Hall. Red kites are often seen overhead north of junction 21. The M25 also forms part of two long-distance E-roads, the E15 and E30, though these routes are not marked on road signs.