The Route of the Welsh Highland Railway

I. WHR (Caernarfon): the Operating Railway, Caernarfon to Dinas

Details of the building of this part of the WHR can be found on a separate page.


Caernarfon is the county town of Gwynedd, and stands at the mouth of the River Seiont on the Menai Strait. The town is perhaps best known for its medieval walls and the imposing castle (above), a major tourist attraction - click for History and more pictures at the Castles of Wales site. You can also find out more about the town and local activities at The former Slate Quay adjacent to the castle was the site of Caernarfon's first railway terminus in the 1820s; the later standard gauge station (closed 1971) on the Bangor-Afonwen line was some distance away, and has been demolished in favour of a supermarket and car parks.

The WHR (Caernarfon) station is close to Castle Square and the castle itself. In the above view of the station we can just see on the left the former premises of De Winton & Co., the Victorian engineering firm famous for their "coffee pot" vertical boiler quarry locomotives. The Castle walls rise in the background.

Major road improvements were carried out at the southern end of the town in the early 1990s. These are adjacent to the point on the trackbed where the route of the former BR Llanberis branch curves off to the south, and a new overbridge was built with sufficient clearance for the railway that was to be constructed later.

Caernarfon to Dinas

The trackbed on this section was opened to the public in the 1980s as part of the Lôn Eifion cycle path. The cycle path has been re-aligned to run alongside the new railway - the two routes are separated by a fence.

The parallel railway and path are used for an annual "Race the Train" charity run, which forms a part of each summer's Caernarfon Festival.

The reconstituted and improved Lôn Eifion deviates slightly from the trackbed in a few spots where clearances are relatively tight. On the first stretch out from Caernarfon station an imaginative repositioning of the footpath outside the railway boundary uses space cleared of undergrowth to give space on the broad railway formation for possible later developments such as a carriage shed and/or sidings.

Almost immediately after passing under the new bridge, the railway crosses the Seiont (above), and passes under a minor road carried by a bridge which has been propped up for many years. The old prop was in the way of the railway, and was thus replaced by a new portal frame steel prop, allowing trains to pass through. From here, the line climbs steeply, bringing it up on to the Arfon Plateau, with views of the mountains opening up on the left, and views down to Caernarfon Bay and the Lleyn Peninsula to the right. The steep gradient out of Caernarfon eases briefly at Hendy Crossing, where no.138 is seen below with the last train of the day.

Major tasks completed in rebuilding the line between Caernarfon and Dinas included substantial repairs to the underbridge at Pont Seiont (on the outskirts of Caernarfon) and to the larger bridge over a road and the Afon [River] Gwyrfai at Bontnewydd (below).

A halt has been constructed here, at the request of residents of the village of Bontnewydd, and is seen here shortly before its opening in 1999.

The view below shows the line crossing Bontnewydd Viaduct, from one of the adjacent footpaths. Even with a brand new railway, it is striking how easily the narrow gauge fits into the landscape.

The line from Caernarfon to Dinas was originally part of the narrow gauge (3'6") Nantlle Railway from 1828 until conversion to standard gauge as part of the Carnarvonshire Railway in 1867. The CR was worked and later absorbed by the London and North Western Railway, and in turn the LMS and British Railways, up to closure of the route from Caernarfon to Afonwen under the Beeching cuts in the 1960s. Another part of the horse-drawn Nantlle line, between Talysarn and the Pen-yr-Orsedd Quarry, survived until 1963. There are places between Caernarfon and Dinas where the 1867 route diverged from the 1828 original, whose remains can still be spotted. On the outskirts of Caernarfon, an old Nantlle tunnel (in remarkably good condition) can be seen adjacent to the propped bridge, while near the bridge at Bontnewydd; eagle-eyed passengers on the landward side of WHR carriages may be able to spot the old Nantlle embankment, and the arch of the original river bridge, which still stands over 130 years after being abandoned. Immediately before Dinas, an abandoned Nantlle cutting can be seen beside the cycle path, and the current railway line crosses it twice in the vicinity.

The track laid between Caernarfon and Dinas in 1997 uses rails and steel sleepers imported from South Africa. The "before" and "after" views below show the formation at an overbridge near Dinas. Inevitably, sites such as this one, where substantial work has been done, look a little raw before vegetation re-establishes itself - as it has done since.


The site of the former Dinas Junction, northern terminus of the old WHR, is now a railway depot and station once again. Dinas (the village is sometimes referred to as Dinas Llanwnda, to avoid confusion with other places in Wales also called Dinas). The site was occupied by a local authority civil engineering depot for many years; however two original buildings remain - the NWNGR/WHR station building, and the goods shed. The station building serves its original purpose and has been restored as far as possible to its original appearance, with the cooperation of the Welsh Highland Heritage Group; the restoration work was honoured with an Ian Allan National Railway Heritage Award in December 2000. The goods shed is at present used for work on carriages and wagons, and for stalls and displays during special events. Later buildings with no likely railway use have been removed or demolished. The view on the right above shows the station on the first day of public operation in October 1997.

The two main platforms are long enough to accommodate 15-coach trains; there is also a shorter bay platform road. The loop changed purpose with the extension to Waunfawr, and is now used as a passing loop when required; trains use the right-hand road in their respective directions, following usual Ffestiniog Railway practice, and the loop is fitted with automatic trailable points. Dinas Works is the engineering base for the line, as it was for the old NWNGR/WHR; once the line is completed there will also be ready access to the Ffestiniog Railway's Boston Lodge Works.

The site of the former WHR running sheds lies in an adjacent yard now also taken over for railway use; The building in the above picture has been modified for use as the new engine shed, and has been extended for this purpose; the far end remains in use by Welsh Water, as an annexe to its large depot adjoining the station. The old WHR passed under the bridge on the left; the new track crosses the scene from the left.

The station platforms at Dinas are on the site of the old standard gauge ones. On departure for Waunfawr the line then curves southwards, on a slightly different formation to the original, and joins the WHR trackbed proper in the smaller southern yard - whose entrance is seen above to the right of Garratt no.138. The slight change of route makes more effective use of the site now that there is only one railway to accommodate, and is less intrusive for adjacent properties; it also avoids major alterations to road access to the site (though a new internal roadway and car park have been built).

A carriage shed has been added, at the Caernarfon end of the site - no. 143 is seen returning its train there at the end of the day's work.

The locomotives burn oil, and take their fuel from a tank installed across the main yard from the platforms, where locos and stock either awaiting or in the process of restoration can be seen; below, 143 on the fuel road is framed by the boiler of no. 134 and the South African brake van.

It is not necessarily obvious to the visitor that the standard gauge infrastructure between Caernarfon and Dinas is actually slightly older than the NWNGR infrastructure from Dinas onwards. Occasionally it requires attention as befits its age, the main example to date being the road bridge crossing the line at the point where it leaves the standard gauge formation at the Waunfawr end of Dinas Station. It had been subject to weight restrictions for many years; the highways authority (Cyngor Gwynedd Council) took the opportunity to rebuild and strengthen it in late 2002, starting after the end of the daily train service.

Shunting operations at Dinas were made more flexible with the introduction of new signalling and a shunt token in May 2004; previously, such work could be awkward, as the line through the Dinas site marks the switch from the Caernarfon-Dinas to the Dinas-Waunfawr token for service trains. Operations Director Andy Savage describes the new system:

There are two signals, out beyond the limits of shunt at each end of the station. At the north (Caernarfon) end it is just over the farm level crossing, at the south (Waunfawr) end just beyond the A487 road bridge.

Each signal is a standard red disc, but with two orange lights at 12 o'clock and 6 o'clock. The lights are normally illuminated, and when they are the line operates as it did prior to their installation.

When you want to shunt Dinas Yards you now remove a token from Dinas station building, You can only do this with permission from Control and when there is no train approaching in the two sections. Once you have permission and take the token out it allows you to shunt out to the limit of shunt boards, and cuts the power supply to the two signals so the lights go out. Any driver then given permission to enter section is warned by control that shunting is taking place, but on approaching Dinas will get a red board and stop until the token is replaced, which you can only do if you are in either the sidings or the loop lines, which are permissively signalled.

Following the extension to the carriage shed a few years ago and with the longer trains now in regular operation on the railway the weak link in the arrangements at Dinas is the length of the carriage release road. The normal operation is for a diesel loco, such as Caernarfon Castle, to withdraw the stock from the carriage shed into the release road. Here the buffet crew stock the train whilst the trains loco for the day is prepared. Whilst in the release road however, even with the diesel right up against the buffer stop there is minimal clearance at the points for other movements in the yard, such as the steam loco going to take fuel. 

In order to rectify this the release road is being extended. The 18th July 2010 saw the Black Hand Gang preparing for that extension.

Preparing to extend the release road and bay platform at Dinas. (Photo: S.Broomfield)Preparing to extend the release road and bay platform at Dinas. (Photo: S.Broomfield)

On the same day the Gang also laid and used a B wagon to test a new 'barrow' crossing that will be used to get supplies to Up trains from the service platform.

Preparing to extend the release road and bay platform at Dinas. (Photo: S.Broomfield)

On the weekend of the 31st July and 1st August 2010 the release road was being extended by half a rail length. This involved digging out the remaining spoil, moving the buffers back and inserting half rail lengths.

The base prepared. (Photo: S.Broomfield)The base prepared. (Photo: S.Broomfield) The half rails in place. (Photo: D.Firth)Caernarfon Castle making use of the extension in the morning. (Photo: S.Broomfield)Caernarfon Castle making use of the extension in the morning. (Photo: S.Broomfield)Caernarfon Castle making use of the extension in the morning. (Photo: S.Broomfield)Hand tamping the new half panel. (Photo: S.Broomfield)Hand tamping the new half panel. (Photo: D.Firth)

[Opening route page] [Caernarfon to Dinas] [Dinas to Waunfawr] [Waunfawr to Rhyd Ddu] [Rhyd Ddu to Beddgelert] [Beddgelert to Porthmadog]

 Back to WHR Project homepage
Authored by Ben Fisher; last updated August 3th, 2010 by Laurence Armstrong