A12 road
:
| A12 Road |
| Northbound exits | Junction | Southbound exits |
| Essex |
| M25, Brentwood A1023 | 11 (M25 J28 - Brook Street) | M25, Brentwood A1023 |
| Brentwood A1023, Mountnessing B1002 | 12 (Mountnessing Marylands) | Brentwood A1023, Mountnessing B1002 |
| No Exit | 13 (Trueloves) | Ingatestone B1002 |
| Margaretting | 14 (Furze Hill) | No Exit |
| Chelmsford A414, Margaretting B1002 | 15 (Webb's Farm) | Chelmsford A414, Margaretting B1002 |
| B1007 | 16 (Stock Road) | B1007 |
| A130, Chelmsford A1114 | 17 (Howe Green) | A130, Chelmsford A1114 |
| A414 | 18 (Sandon) | A414 |
| No Exit | 19 (Boreham) | Chelmsford A138 |
| Hatfield Peverel | 20a (Hatfield Peveral South) | No Exit |
| No Exit | 20b (Hatfield Peveral North) | Hatfield Peverel |
| Witham B1389 | 21 (Lynfield Motors) | No Exit |
| No Exit | 22 (Coleman's) | Witham B1389 |
| Kelvedon B1024 | 23 (Kelvedon South) | No Exit |
| No Exit | 24 (Kelvedon North) | Kelvedon B1024 |
| Braintree, Stansted A120, B1408 | 25 (Marks Tey) | Braintree, Stansted A120, B1408 |
| A1124 | 26 (Eight Ash Green) | A1124 |
| Colchester A133 | 27 (Spring Lane) | No Exit |
| Harwich, Clacton A120, Colchester A1232 | 29 (Ardleigh Crown) | Harwich, Clacton A120, Colchester A1232 |
| Suffolk |
| B1029 | 30 (Park Lane Birchwood) | B1029 |
| East Bergholt | 31 | East Bergholt |
| Capel St. Mary | 32a (Capel St. Mary South) | Capel St. Mary |
| C475 London Road | 32b (Bentley Longwood) | C475 London Road |
| London, Ipswich A14, A1214 | 33 (A14 J55 - Copdock Mill) | End of duplex with A14 |
The
A12 is a major road in
England, a
trunk road for most of its length, running from
London to
Great Yarmouth in
Norfolk.
Starting at the
Blackwall Tunnel, it heads north, then north east through
Leyton,
Leytonstone,
Gants Hill and
Romford, then into
Essex, passing
Brentwood,
Chelmsford and
Colchester. In
Suffolk, it passes
Ipswich,
Woodbridge and
Saxmundham, then follows the coast through
Lowestoft and
Gorleston before entering Norfolk and ending at Great Yarmouth.
The section from the Lea Interchange to Leytonstone, which is all
dual carriageway, was built in the
1990s following the removal of
protestors. This section has an underpass at the
Bow Interchange roundabout, a junction with the
A11. The old section as far as
Wanstead was rebuilt as a dual carriageway. Prior to that, the A12 started at the
Green Man Roundabout at Leytonstone, and was single carriageway west of
Wanstead tube station. It now has an underpass at that roundabout, which again is a junction with the old A11.
East of Wanstead, the A12 runs roughly due east. It is known as
Eastern Avenue, then Eastern Avenue West and Eastern Avenue East until it reaches
Gallows Corner in the
London Borough of Havering, just east of Romford, where the
A127 starts. It now veers roughly north-eastward, because it starts to follow the course of the
Roman road from Colchester to London; the Romans started building this road from Colchester, their original capital for the province. However, the 2.5 mile (4 km) stretch from Gallows Corner to the junction with the
M25 motorway, called Colchester Road, is still perfectly straight. The M25 junction is number 28; it also marks where the A12 crosses the boundary from London to Essex.
Originally, the A12 followed the Roman road fairly closely hence was fairly straight, but there are now several town bypasses, so the road through Essex looks quite wavy on a map. The A12 formerly went through Brentwood,,
Mountnessing,
Ingatestone,
Margaretting, Chelmsford,
Boreham,
Hatfield Peverel,
Witham,
Ramsgate,
Kelvedon,
Copford,
Stanway and Colchester, but these are all now bypassed, and the A12 is close to
motorway standard for its whole length in Essex.
Colchester
Built in the
1970s, the A12 Colchester bypass provides an uninterrupted dual carriageway where the national speed limit (70 mph or 113 km/h) applies.
Before the 1970s, the A12 took a route much closer to Colchester itself, and although still a bypass it consisted of urban single carriageways with roundabouts and pedestrian crossings. The old bypass is, of course, still in existence – the western half is now part of the
A1124 and the eastern half part of the
A133.
The Suffolk stretch of the A12 starts with the
Capel St Mary by-pass. Originally the route from the Northern end of this bypass ran through the villages of Washbrook and Copdock and into
Ipswich. When Ipswich's Southern by-pass was built in the early
1980s, the route picked up from the northern Capel St Mary junction (now numbered 32b), to pass to the West of the original line -- this allowed the relevant ground works and interchanges to be completed with minimal traffic disruption. The old
dual carriageway through Washbrook and Copdock is blocked off at White's Corner and was renumbered to be the B1113. A footpath still exists which enables passage underneath the A14.
Ipswich
The old route through Ipswich was renumbered as the
A1214 following construction of the Ipswich Southern By-pass. The old route is more locally known by the road names, notably "London Road" to the Town Centre and Woodbridge Road out the other side.The Ipswich Southern By-pass allows the A12 to multiplex with the
A14 to Seven Hills Interchange, ironically 7 miles from the Copdock junction, where the A12 reappears and heads North with at-grade roundabout junctions past BT Adastrial Park at
Martlesham and around the
Woodbridge bypass.
For most of its remaining length through Suffolk the A12 is a
single carriageway road and in many places its speed limit is less than the national limit, for example as it passes through towns and villages. During 2003/2004 some of these speed restrictions were further reduced from 40mph to 30mph.
Lowestoft
The A12 runs through Lowestoft for about 5 miles (8 km) on urban 30 mph (48 km/h) limited roads. A further impediment is the harbour bridge, which has three lanes, the centre lane operating as a one-way addition to whichever direction of flow is deemed greater according to time of day.
An alternate route avoiding Lowestoft is available through
Oulton Broad (the town of), but again via urban roads and a bridge.
The presence of these bridge choke points can cause serious disruption to north-south trunk traffic, especially when local traffic is added during rush hours.
A proper bypass for Lowestoft would have to be well to the west, even to the west of
Oulton Broad (the body of water), and its route would have to consider the great extent of marshland in that area. For that reason an often discussed compromise is a third bridge, crossing Lake Lothing, linking the sections of urban spine-road that run approximately along the western edge of Lowestoft.
Gorleston
From a point just south west of the mouth of the
River Yare, northwards to the point where it crosses the River Yare in
Great Yarmouth, the A12 now follows the route originally used by the railway line from Lowestoft to its terminus at Haven Bridge where Great Yarmouth's Southtown Station used to be.
*
Society for All British Road Enthusiasts entry for the A12
