South Wales lines - General Information

Description of line
West of Severn Tunnel Junction the Great Western mainline continues through the major stations of Newport (just after a junction with the line) Cardiff Central, Bridgend, Port Talbot Parkway and Neath to Swansea. Around Cardiff is the 'Valley Lines' commuter network consisting of several lines north of the GWML^▸ and the Vale of Glamorgan line, which takes a more southerly route between Bridgend and Cardiff with branches to Penarth and Barry Island. Leaving Newport eastbound a line heads north away from the GWML to Hereford, used by the current North Wales to South Wales services, among others.

Swansea station is a terminus, however as well as the GWML towards Cardiff there is a line which continues westwards. In this direction, a section of single track (including Gowerton station) takes the line part of the way to Llanelli, where there is a junction for the Heart Of Wales Line to Shrewsbury (trains from Swansea need to reverse at Llanelli station to access the Heart Of Wales Line). Between Port Talbot and Neath, near the minor station at Briton Ferry, there is a so-called freight-only line known as the 'Swansea District Line' which bypasses Swansea and Neath stations to connect with the Heart Of Wales Line. The Swansea District Line, the southern part of the Heart Of Wales line that links it to Llanelli and Llanelli station itself are all double tracked. Continuing west from Llanelli the line from Swansea remains double and eventually reaches Carmarthen, where there is a bypass line avoiding the station, which has been a terminus since the closure of several northbound routes. Most trains do not use the bypass line but either terminate or reverse in the station.

The line west from Carmarthen first reaches Whitland where there is a junction for the single track branch to Pembroke Dock (which has a passing loop at the station for the holiday resort of Tenby). The double track line continues west through two request stops. Near the second (Clarbeston Road) the double track stops and there is a two-way junction. In one direction the railway serves Haverfordwest (where there is a passing loop), Johnston (request stop) and Milford Haven. There were 3 oil refineries near Milford Haven, each with a freight-only branch line, only one of these is still an oil refinery, although only one of the 3 freight lines shows on the map as having been dismantled. Back at Clarbeston Road the other line heads for Fishguard Harbour, all intermediate stations on this line are closed.

First Great Western journeys made within Wales
The FGW^▸ services that penetrate furthest into Wales are INTERCITY 125 express services from London Paddington. As far as regular services are concerned there is an hourly between Paddington and Swansea for much of the day Monday-Saturday. These trains form roughly half of an even more frequent FGW INTERCITY 125 service between Cardiff Central and London Paddington. Carmarthen receives a single train from Paddington on weekday evenings with a morning departure to Paddington.

On summer Saturdays at Carmarthen there are three departures to, and two arrivals from, London Paddington. Of these, 1 service from Paddington continues to Pembroke Dock and 2 of the services to Paddington originate from Pembroke Dock. These services are balanced by a service to Pembroke Dock from a point other than Paddington (probably Swansea). Some of the Pembroke Dock INTERCITYS call at the tiny stations on the Pembroke Dock branch, while others don^t. On Sundays there are three direct services each way between Carmarthen and Paddington.

Other First Great Western services in Wales come no further west than Cardiff Central. These include the Cardiff - Portsmouth services (run using class 158 DMUs^▸ ) and services to Taunton.

Service offered
Most other services are currently operated by Arriva Trains Wales except for Cross Country services into England from Cardiff Central. The following regards Monday to Saturday services. West of Cardiff, apart from valley lines trains and local stopping services between Cardiff and Swansea, Arriva^s services include a two-hourly service to Manchester from Carmarthen and another two-hourly Manchester service from Milford Haven, making this service hourly between Manchester and Carmarthen. The Manchester trains are generally semi-fast services. There is also a two-hourly ATW^▸ stopper service between Swansea and Pembroke Dock, some elements of which are replaced by the FGW summer Saturday service. Heart Of Wales services generally start from Swansea, reverse at Llanelli, and continue to Shrewsbury, there are only a few trains per day (4 I think) each way.

The final element of South-West Wales passenger services is the Fishguard Harbour runs. There is one train to Fishguard Harbour from Cardiff Central calling at only Llanelli and Whitland, using both the Swansea district line and Carmarthen avoider (I^m 99% sure this is the only passenger service that does so). This train arrives at Fishguard at about 13:15 and departs 15 mins later, calling at Whitland, Carmarthen, Llanelli and Cardiff and continuing to Cheltenham Spa as one of the normal Cardiff ^ Cheltenham stoppers. It uses the Swanswa district line in this direction too. Despite the very limited stopping pattern in both directions this train is normally a class 150 unit. The only other service to Fishguard is in the middle of the night and runs to/from Swansea.

Known issues
^ Single track between Swansea and Llanelli is a capacity bottleneck. Plans to re-double the line in connection with renewal of a viaduct on the section exist
^ Fishguard^s two trains per-24hours are timed to meet ferries, not the needs of Fishguard residents. There are also 2 (summer only) ferry sailings without train connections
^ Apart from the day Fishguard train very few services use the district line which not only avoids the capacity bottleneck but also has the potential to cut journey times by 15mins without needing linespeed improvements
^ Trains on the Pembroke Dock services tend to have a long wait at Pembroke Dock to time their return trip to allow them to pass the next service at Tenby, the only passing loop on the branch

Thanks to Rhydgaled for this! - Phil