IT FORMS one of 20 separate and equally important bridges along the Settle-Carlisle line, though little has been written or is known about Dent Head viaduct, created under the watchful eye of engineer John Sydney Crossley between 1869 and 1875.

When discussing the bridges along the line, the most well known is the huge structure at Ribblehead, with few mentions given to the structure near Dent.

Here, Hannah Kingsbury, historic environment apprentice with the Yorkshire Dales National Park Authority writes about the feature in her blog on the Authority's website.

When you think about the Settle-Carlisle railway line the most known viaduct is the one at Ribblehead – the Batty Moss viaduct.

It is still a working railway and after crossing this viaduct, the line enters Blea Moor Tunnel (about 2,400m long and 150m below the moor) before emerging onto Dent Head Viaduct, just on the outskirts of the Craven district.

This carries the line over Fell End Gill. It is suggested that a tramway existed prior to the railway which ran from Batty Moss to Dent Head Viaduct. The tramway would have been built to transport bricks directly from the brickworks to the construction site at Dent.

About a mile down the line is Artengill Viaduct. This was one of the most difficult viaducts to build and is set into the limestone bedrock through shafts 50ft long which had to be driven through unstable shales.

It is also one of the few viaducts that did not use bricks in its arch construction. The construction of the Settle-Carlisle Railway was a massive project undertaken by Midland Railway which took over six years and today is the longest conservation area in the UK.

During construction of Dent Head viaduct, one contractor had to give up as a result of underestimating the terrain and the weather. Apparently Dent Head has almost four times the rainfall of London.

The Dent Head Viaduct was built between 1869 and 1875. It follows a slightly curved line on a north-south(west) axis.

It is constructed from massive blocks of rock-faced sandstone, which is mostly coursed but some is snecked. It has 10 tall round-headed arches, 100 feet high, on battered rectangular piers – the ones in the centre being broader than the others.

There are brick soffits to the arches, with rusticated sandstone voussoirs. There are now three tie-plates to each arch to help reinforce the structure. The parapet has a moulded string course and rounded coping.

In the shadow of the viaduct is an 18th century packhorse bridge. It is named Dale Head Bridge on the 1st edition OS map.

It is constructed from sandstone rubble. It has a low segmental arch with one ring of narrow rubble voussoir stones. There is a grassy track over it. Packhorse bridges were constructed to carry horses loaded with side-bags or panniers across a river or stream. In this case Fell End Gill. Packhorse routes were the trade routes that formed the major transport arteries of Great Britain until the coming of the turnpike roads and canals - and railways!

The small packhorse bridge under the viaduct carries water from the nearby hills which runs finds its way into the River Dee and can form a torrent during heavy rain.

Dent Head viaduct has been designated a Grade II listed and scheduled monument and sits within a conservation area.

For visitors there is no access underneath the bridge itself but there is a layby next to the bridge and there is a great view of the viaduct driving into Dentdale from the B6255 road.

For walkers it is found on OS grid reference SD 777 844.

The viaduct has even earned itself a review on Trip Advisor from a French visitor in July last year who wrote: "Superb viaduct which is worth the detour, in addition the region is of an incredible calm. No tourists in every corner, easy parking, free, go for it!"

For those unfamiliar with the construction terms of the masonry used in its building here is a handy glossary:

Viaduct – A viaduct is a long bridge-like structure, typically supported using a series of arches, which carries a road or railway across a valley/other low ground

Snecked – Snecked walling is the term given to a wall constructed of stones, usually (roughly) squared, of three distinct bed heights and follows a consistent bonding arrangement

Soffits – They are generally the underside of any construction element, in this context the underside of the arch

Rusticated – Rustication is a type of decorative masonry achieved by cutting back the edge of stones to a plane surface while leaving the central portion of the face rough or projecting. It often contrasts to the finish of the other stone used in the construction. In this case they are quite weathered.

Voussoirs– A voussoir is a wedge-shaped or tapered stone used to construct an arch (they are visible on the face of the arch)

Parapet – The parapet is a low protective wall along the edge of the bridge.

String course – This is a horizontal band or course that projects or is flush with the wall and often moulded. It is often used as a line of demarcation, in this case between the viaduct and the parapet.

Coping – The coping is the capping of the wall – the top course of the wall.