Puneet Varma (Editor)

A55 road

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East end:  Chester
Primary destinations:  Conwy Bangor
Start  Holyhead
West end:  Holyhead
Length  140 km
Connects to  M53 motorway
A55 road

Driving through conwy tunnel north wales uk a55 road expressway

The A55, also known as the North Wales Expressway (Welsh: Gwibffordd Gogledd Cymru) and the Chester to Bangor Trunk Road, is a major road in Britain. Its entire length is a dual carriageway primary route, with the exception of the point where it crosses the Britannia Bridge over the Menai Strait and several short sections where there are gaps in between the two carriageways. All junctions are grade separated except for two roundabouts — one east of Penmaenmawr and one in Llanfairfechan. The road originally ran from Chester to Bangor but was extended parallel to the A5 across Anglesey to just outside Holyhead Docks in 2001. The road improvements have been part funded with European money, under the Trans-European Networks programme, as the route is designated part of Euroroute E22 (Holyhead - Leeds - Amsterdam - Hamburg - Malmö - Riga - Moscow - Perm - Ekaterinburg - Ishim).


Map of A55, Bangor LL57, UK

The A55 is sometimes called a motorway, because of its appearance, although it is not officially a motorway.

A55 road in wales video

The Chester Southerly Bypass

The A55 begins at the end of the M53 motorway near Chester, where it is known as the Chester Southerly Bypass, crossing the River Dee and the Welsh border before passing close to Broughton then passing north of Buckley , Penyffordd and Northop. There is a major climb westbound between Broughton and Buckley (Junctions 35a to 35) though with no crawler lane. Junction 34/33b is point at which the A494 converges and then diverges with the A55. The road briefly has a three-lane section as westbound traffic from Queensferry can leave towards Mold. In the eastbound direction another short three-lane section allows vehicles to join the A494 or exit onto the A55 to Chester. Traffic taking the A55 into England must negotiate a tight 270 degree speed-limited single lane curve to climb up and over the A55/A494. Plans to upgrade the A494 between this junction at Ewloe and Queensferry were rejected by the Welsh Assembly Government on 26 March 2008 due to their scale.

Ewloe to Colwyn Bay

From Ewloe, the road is relatively flat until after Northop when it climbs up onto the flanks of Halkyn Mountain range, passing to the southwest of Holywell with major climbs between Northop and Halkyn (Junctions 33 and 32b) and Halkyn and Holywell Summit (Junctions 32 and 31). This section of road is notorious for poor weather conditions including fog, ice and snow in winter months. In fine weather, however there are extensive views over the River Dee estuary to the Wirral Peninsula, Liverpool and beyond. The highest part of the road is in the vicinity of Brynford at around 790 feet (240 m). The steep descent towards St Asaph is down the new Rhuallt Hill (Junctions 29 to 28), which also provides the first views of the mountains of Snowdonia in the far distance. There is a crawler lane on Rhuallt Hill for eastbound traffic. The road bypasses St Asaph to the north, and runs past Bodelwyddan and Abergele to reach the North Wales coast at Pensarn (Junction 23A). From here onwards to Bangor, the route is close to the North Wales Coast railway.

Colwyn Bay Bypass

Two sections between (Junction 23) Llanddulas to (Junction 17) Conwy are signed as a 70 mph (110 km/h) speed limit because they are classed as non-motorway special roads. Unlike other sections of the A55 that have National Speed Limit (NSL) signage and are accessible to all motor vehicles, motorway restrictions (although it's not a motorway) apply on these stretches of road e.g. no pedestrians, learner drivers, farm vehicles etc. This is because these sections were built under legislation applicable to the building of motorways. But as they are not part of either the UK motorway network or are classed as an ordinary highway (public right of way), the national speed limit does not apply so 70 mph (110 km/h) signs (the maximum speed permitted on UK roads) are used instead.

A 50 mph (80 km/h) limit remains in force through the Colwyn Bay bypass (Old Colwyn to Mochdre). The restriction was imposed for several reasons. First as a safety precaution because the slip-roads on this stretch are unusually short due to the road's design. Part of it was built on a narrow swathe of land through the town that was once the North Wales coast railway; Colwyn Bay had to be rebuilt and the track bed realigned to complete the underpass. The former four-track railway was reduced to two more northerly tracks to make space for the road. Second the reduced speed limit was intended to reduce road noise for residents. However, since the completion of the Colwyn Bay bypass, the lower speed limit has been an unpopular decision with drivers.

The Conwy Bypass

The crossing of the estuary of the River Conwy is by means of an immersed tube tunnel, the first of its kind constructed in the United Kingdom.

The decision to construct an immersed tube tunnel bypass followed an extensive public consultation, named the Collcon Feasibility Study. This ruled out another bridge by the castle on aesthetic grounds, since it would have damaged the view of the world heritage site Conwy Castle, and the two bridges by Robert Stephenson and Thomas Telford. Another alternative bridge crossing was proposed at Deganwy, but this too was ruled out for aesthetic reasons. An inland alternative with heavy grades which would have passed over Bwlch y Ddeufaen pass at 430 metres (1,410 ft), following the old Roman road, was also worked up but rejected for cost and utility reasons.

The tunnel was constructed by a Costain/Tarmac Construction joint venture, as pre-formed concrete sections, and then floated into position over a pre-prepared trench in the bed of the estuary. The 3 million tonnes of silt and mud extracted to create the trench in which the tunnel sections sat, were vacuumed to one side of the construction site, as to let them drift down river would have harmed the large mussel fishing beds downstream. The silt was deposited upstream of the bridge at Conwy which created a large new area of low-lying land which was subsequently given to the RSPB for a wildlife preserve. The casting basin for the tunnel sections was later converted into a new marina in the lower estuary. Because of the valuable fishery in the river and also because of the history of heavy metal mining in the catchment of the river, extensive ecological assessments were made both prior to the construction of the tunnel and subsequently. These studies finally concluded that no significant environmental damage had been caused.

After five years of construction, the tunnel was opened in October 1991 by Queen Elizabeth II, the tunnel initially had an advisory 50 miles per hour (80 km/h) speed limit, but this was dropped in 2007 as accidents were rare in the tunnels.

Penmaenbach and Pen-y-clip tunnels

Leaving Conwy in a westerly direction, the construction of this section has involved major civil engineering works because it crosses two major headlands: Penmaenbach Point and Penmaenan Point. Work has involved the cutting of several hard rock tunnels beneath the sea cliffs.

The first to be built in 1932 was the Penmaenbach Tunnel which carried motor traffic to Penmaenmawr. Two smaller tunnels through Penmaenan Point, opened 1935, carried the road onto Llanfairfechan. This new route, carrying traffic in both directions, relieved the original coach road built by Telford in the early 19th century. Cut into the cliffs by hand, this narrow, winding route hugged the contours around both steep headlands. Telford's route has now been converted into a cycleway across Penmaenbach and Penmaenan Points. Originally at the western end (Llanfairfechan) of the modern Pen-y-Clip tunnel, access was only allowed in an easterly direction because travelling the other way would mean heading the wrong way up the eastbound carriageway. However, in 2011 a purpose-built bridge - over the westbound carriageway - was constructed to allow unrestricted access to cyclists and walkers.

The 1930s alignment was used until a new two-lane Penmaenbach Tunnel opened in 1989 to carry westbound traffic. Eastbound traffic would now travel through the 1932 Penmaenbach Tunnel using both its original lanes. Four years later, work to build the Pen-y-clip tunnel was completed. Like at Penmaenbach it carried westbound traffic while the original road carried vehicles in the opposite direction. Both new routes were subject to an advisory 50 mph speed limit until these were lifted in 2007 as there had been few accidents.

However traffic travelling eastbound on the 1930s cliffhugging route still faced speed restrictions at both tunnel locations. For instance the eastbound carriageway at Penmaenbach is subject to a 30 mph (50 km/h) speed limit due to sharp curves and double white lines nominally preclude lane changing. Plans to rectify the awkward alignment by building another tunnel parallel to the current westbound tunnel (as originally intended when the westbound tunnel was proposed) have been discussed for several years. The Recent work (late 2007) at Penmaenbach eastbound has seen the erection of gantries to close lanes when bidirectional working is in place.

Penmaenmawr to Anglesey

Some sections of the rest of the route are of lower standard than that of those further east. Some traffic leaves for major holiday destinations such as Caernarfon or the Llŷn Peninsula, though much continues on to the port of Holyhead. As such part of the route is not classed as clearway and has two at grade junctions (roundabouts), Penmaenmawr (Junction 16) and Llanfairfechan (Junction 15). The Bangor bypass, in which the road previously terminated and became the A5 regains high standards and is such through the Anglesey section, bar the Britannia Bridge, which is a single carriageway deck above the North Wales Coast railway over the Menai Strait. In 2007 the Welsh Assembly Government undertook a consultation to determine which of four options would be preferred for a second crossing. This section intersects with the A487 towards Caernarfon, and the west coast of North Wales.


The final section of the A55 to be constructed was the Anglesey section. This 20 mile (32 km) section from the end of the Llanfairpwll bypass to Holyhead Harbour was constructed as Private Finance Initiative scheme where the builders, a Carillion / John Laing joint venture, earn a shadow toll based on usage and lane availability. They also have to maintain the road for the extended period of their shadow toll agreement. When travelling eastbound along this section there are fine views of Snowdonia. The approach to Holyhead required major work with a new section over the sea paralleling the Stanley Embankment that carries the original A5 and the North Wales Coast railway.

Planned improvements

Work started in early 2017 on the upgrading of the 1960s built substandard section of dual carriageway west of Abergwyngregyn from Tai'r Meibion towards Tan-y-lon, which is relatively narrow and prone to flooding. This includes mention of improvements to the A55 including the grade separation of the two roundabouts at Penmaenmawr and Llanfairfechan planned to be completed by 2021. In November 2012, the Welsh Government published two more detailed studies looking at options to improve transport in the North East Wales and the A55 / A494 areas. Possible changes to be considered further include

  • applying managed motorway concepts
  • providing hard shoulders
  • providing crawler lanes at key points
  • redesigning and improving slip roads.
  • History

    The A55 partly follows the alignment of the Roman road from Chester (Deva) to Caernarfon (Segontium), particularly from Junction 31 to 30 and Junction 13 to 12. Between Chester and Holywell the alignment of this road is uncertain and between St. Asaph and Abergwyngregyn, the Roman road followed an inland route, via Canovium Roman Fort at Caerhun, avoiding the difficulties of the crossing of the Conwy estuary and the cliffs at Penmaenbach and Pen-y-Clip.

    A55 opening dates of major improvements

  • Unknown date 1930s? Ewloe to Northop avoiding Northop Hall
  • Unknown date 1930s? Northop Bypass
  • Unknown date 1930s? Holywell Bypass
  • Unknown date 1930s? St. Asaph to Rhuallt dual carriageway
  • Unknown date 1930s? Short section of 'experimental' concrete road west of St Asaph
  • 1932 Penmaenbach Tunnel
  • 1935 Pen-y-Clip Tunnels
  • 1958 Conway new bridge avoiding Telford's suspension bridge
  • 1960s Tai'r Meibion to Tan-y-lon dual carriageway east of Bangor
  • 1964? Ewloe roundabout (part of the A494 Queensferry to Ewloe dualling, the 'Aston Bypass')
  • Unknown date 1965? Llysfaen dualling
  • 1968 Abergele Bypass
  • 1970 St. Asaph Bypass
  • 1975 Northop Hall Crossroads to East of Gables
  • 1976 Coed-y-Cra to Chaingates (Holywell)
  • 1976 Chester Southerly Bypass (terminating at Broughton)
  • 1980 Britannia Bridge and link roads
  • December 1980 Holywell By-Pass (Stage 1)
  • March 1981 Diversion East of Abergele
  • December 1983 Bangor By-Pass
  • September 1984 Hawarden By-Pass (from a point east of Broughton on the Chester Southerly Bypass to Northop Hall)
  • December 1984 Llanddulas to Glan Conwy (Colwyn Bay By-Pass, Stage 1)
  • June 1985 Llanddulas to Glan Conwy (Colwyn Bay By-Pass, Stage 2)
  • October 1986 Holywell By-Pass (Stage 2)
  • December 1986 Bodelwyddan By-Pass
  • June 1989 Penmaenbach Tunnel
  • June 1989 Northop By-Pass (Northop Hall to Halkyn)
  • October 1989 Penmaenmawr and Llanfairfechan By-Passes (excluding Pen-y-Clip Tunnel)
  • May 1990 Travellers' Inn Improvement
  • 1991 tunnel crossing of the River Conwy
  • June 1991 Extension of Chester Bypass to M53 (Junction 12)
  • May 1992 Rhuallt Hill Improvement
  • October 1993 Pen-y-Clip Tunnel
  • October 1994 Abergwyngregyn Improvement
  • 16 March 2001 Anglesey section (Llanfairpwll to Holyhead) including Llanfairpwll by-pass
  • 2000/2004 Penmaenmawr eastbound slip road and grade separation at the summit of the Rhuallt Hill
  • 2004 Improvements to railway underbridges and cliffs at Penmaenbach (eastbound)
  • 2007 Alterations to roundabout at Llanfairfechan and bidirectional road indicators at Penmaenbach (eastbound)
  • 2008 New overbridge between Junction 32A and 32B for improved local access
  • Services

    There are two large services on the A55, along with numerous other petrol stations at the side of the road. The two major services are:

    Bangor Services
    (At J11) - Little Chef, Burger King, Travelodge, Esso, Costa Express

    Gateway Services
    Eastbound (After J33A) - Little Chef, Little Chef Express, Travelodge, Shell, Costa Express
    Westbound (After J33B) - Costa Coffee, Subway, McDonald's, OK Diner, Holiday Inn, Shell, Costa Express, Deli2Go


    A55 road Wikipedia