Bell Common is a settlement in Essex

Essex

Essex is a ceremonial and non-metropolitan county in the East region of England, and one of the home counties. It is located to the northeast of Greater London. It borders with Cambridgeshire and Suffolk to the north, Hertfordshire to the west, Kent to the South and London to the south west...

, England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 and forms the southern part of the town of Epping

Epping

Epping is a small market town and civil parish in the Epping Forest district of the County of Essex, England. It is located north-east of Loughton, south of Harlow and north-west of Brentwood....

.

Tunnel

The Bell Common Tunnel is a covered section of the M25 motorway

M25 motorway

The M25 motorway, or London Orbital, is a orbital motorway that almost encircles Greater London, England, in the United Kingdom. The motorway was first mooted early in the 20th century. A few sections, based on the now abandoned London Ringways plan, were constructed in the early 1970s and it ...

 in Bell Common. The route of the motorway at this point was forced into a very narrow gap between the ecologically important Epping Forest

Epping Forest

Epping Forest is an area of ancient woodland in south-east England, straddling the border between north-east Greater London and Essex. It is a former royal forest, and is managed by the City of London Corporation....

 to the south and the settlements to the north. The decision was therefore made to put the motorway underground. The tunnel is 470 metres long and was constructed between 1982 and 1984 using the cut and cover method.