THE Scots Dyke has been called “one of the most remarkable earthworks in the whole country”, and yet it is very enigmatic.

No one really knows who built it, or why, or when, but those with vivid imaginations can trace it more than 100 miles from a mound beneath which a crock of gold is reputedly buried in the Yorkshire Dales, through County Durham and right up to the Firth of Forth.

We mentioned it a couple of weeks ago in this space, and we are extremely grateful to John Backhouse for sending us a copy of a paper presented to the Newcastle Society of Antiquaries in 1905 by William Wooler, the eminent Darlington historian, who had spent many years studying maps in search of a tantalising clue and then traipsing the countryside in search of a ditch.

The dyke, which is also known as the “catrail”, runs from Grinton, in Swaledale, around Richmond, over the Tees at Gainford, up Weardale to Allenheads and then north-west through the Kielder Forest to the Scottish border before heading even further north.

Most speculation suggests that it was a 6th Century boundary between the kingdom of Rheged, that was based in the west on Carlisle, and the Anglian kingdom of Deira to the east.

Two boys in November 1960 exploring the recently excavated Scots Dyke near the Brigantes Stanwick camp

Two boys in November 1960 exploring the recently excavated Scots Dyke near the Brigantes' Stanwick camp

But Mr Wooler disagreed. “I say emphatically that the Catrail, Scots Dyke or Black Dyke was a huge military work and not a mere boundary dividing kingdoms or tribal territories,” he said. “This stupendous earth work I believe to have been constructed in a vain attempt to repel the second Roman invasion of Britain and may have been formed between 55BC, the date of the first invasion, and the second invasion in AD43.”

All sources agree that Maiden Castle, on Harkerside, on the south side of the Swale near Grinton, was extremely important to the dyke. On its east side, it is protected by at least two manmade ditches which run down to the Swale and are still clearly visible.

“The purpose of the site is as uncertain as its age,” says Chris Park in his 2014 book, The Story of a Dale.

Most people seem to think it is a defensive structure into which herdsmen on the valley floor would have retreated when under attack. It contains the remains of stone structures and several burial barrows. Under one of them lies a crock of gold still waiting to be unearthed.

The boundary stone beside the Scots Dyke on the B6271 from Brompton-on-Swale into Richmond. The dyke is at least 1,500 years old but still acts as the eastern boundary of Richmond

The boundary stone beside the Scots Dyke on the B6271 from Brompton-on-Swale into Richmond. The dyke is at least 1,500 years old but still acts as the eastern boundary of Richmond

From Grinton the dyke – which when dug was 28ft wide with ramparts up to 10ft high on either side – runs east to Hauxwell before going north through Hipswell to cross the Swale near Easby Abbey. Its course north is followed by a footpath which to this day marks the eastern boundary of Richmond.

“In the old boundary rolls of the borough of Richmond, it is called the road dyke,” said Mr Wooler. “Indeed it is not improbable that the banks were used at an early period as a roadway for travelling through the country, at that time largely marsh and moor, and the discovery in its vicinity of many decayed iron hoops of ancient chariot wheels seems to countenance this belief.”

The dyke can be traced going to Gilling West, where the main street may be built on top of it, before heading up the bank to Melsonby, where it is commemorated in a street name.

It goes around the Brigantes’ tribe’s Stanwick fort, perhaps the home of the 1st Century queen Cartimandua. Here the deep remains of the dyke are quite spectacular.

Still heading north, it forded the Tees at Barforth, near Gainford, before climbing out of the village on a road still known as Ford Dike Lane up to Ingleton. It went across Cockfield Fell, over the River Wear at Witton-le-Wear before heading up the north side of Weardale – Wolsingham, Stanhope, Weardale – before heading north-west to Scotland.

As Harry Speight said in his 1897 book, Romantic Richmondshire, it was a “stupendous effort of labour”.

All along its length, signs of it still remain as footpaths, boundaries, street names, dirty great ditches or lost crocks of gold, although in most places, Father Time and centuries of human farmers have done their best to wear down the ramparts and fill in the fosse.