The
M25 or
London Orbital Motorway is a
motorway that almost encircles
Greater London, England (with the exception of
North Ockendon), in the United Kingdom. A narrower concept was first mooted in the 1960s as part of the plan to build
four ring roads around London. A few sections, based on the abandoned
London Ringways plan, were constructed in the early 1970s and it was completed in 1986.