A BOOK celebrating the Border between Scotland and England has been written by SNP MSP Alasdair Allan to raise money for charity.

Tweed Rins Tae The Ocean is also a response to former Tory MP Rory Stewart’s contention that the Border is not “natural”.

The book follows Allan’s 100-mile walk along the line from east to west and gently explores the history, literature and language of what he believes is the oldest national land border in the world.

The title takes its inspiration from a line of the Burns song, Sic A Parcel Of Rogues which bitterly protested against the 1707 Union, and the book is not only the result of Allan challenging himself to walk the Border line but also to read a way through its literature.

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Although he is MSP for the Na h-Eileanan an Iar constituency and has lived on the Western Isles for 14 years, Allan grew up just 18 miles from the Border and his family “from time immemorial” are from the area, working as farm labourers until just a couple of generations ago.

He said the reality and distinctiveness of the Border had always ­fascinated him and he was partly ­motivated to walk along it and write the book in answer to Stewart.

“I read a book not long ago by Stewart which was a very good book in some ways but he was making this ­argument that basically Scotland wasn’t really there and it was only the SNP that were telling us it was there,” said Allan.

“He made that argument by walking along the Border to try to prove it wasn’t there so I suppose my book is a bit of an antidote to that although it’s not the only reason I wrote it.

“However I think there is a definite move to be suspicious of expressions of Scottish culture in the Tory party and the Border in its own way is an expression of Scottish distinctiveness. I think that is worth celebrating and that is what my book tries to do.”

He added: “It should be no surprise that a book by a politician about a political boundary offers occasionally opinionated views. However, I hope that the account of my walk from Berwick to the Solway Firth will be appreciated by anyone who likes dry humour and wet weather.”

ThunderPoint Publishing, originally based in South Uist, are to publish the book this autumn with a foreword by author, broadcaster and mountain walker Cameron McNeish.

He said: “There is nowhere else in Scotland I sense an ‘uncanny watchfulness’ as intensely as I do in the Borders. It lurks on every hilltop, in every cleuch and in every castle ruin, and Alasdair Allan has, almost magically, captured this essence of the Border.”

Walking with friends, Allan made the journey in stages over two years, researching the literature as he went.

“I tried to read everything I could that was related so I read through a lot of Walter Scott and James Hogg but I found all sorts of stuff including an opera about Gretna Green, would you believe, and I have tried to tie it together in a reasonably light-hearted way,” he said.

“For me it was a chance to read up about the Border Reivers and to read surprising bits of literature about the Border such as the fact that Alasdair Gray wrote science fiction set in 23rd-century Selkirkshire.”

While there have been small ­changes, the Border is still exactly where it was in the 13th century, according to Allan.

“It’s difficult to find anywhere that has a land border that sort of age apart from ourselves and Andorra,” he said.

Although he knew the eastern half of the Border well, the western half was new to him and he was intrigued by story of the Debateable Lands, a 10-mile stretch of country of unclear nationality up until the 16th century.

Throughout the walk, Allan tried to follow the line of the Border as closely as possible which occasionally brought problems.

“There are points in the book where I recommend the reader does not ­follow my way because there are one or two places where I got lost,” he said.

“I followed the Border so ­rigidly and dogmatically that I ended up

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following it through forests and ­falling down holes. Some of the ­places I went were not very sensible and I did ­manage to injure one of my ­walking companions who fell down a hole. They are still friends, ­amazingly.”

A Gaelic speaker, Allan’s interest in languages is reflected in the book.

ThunderPoint’s editorial director Seonaid Francis, said it was “warmly-written and entertaining, bursting with humour and a deep-rooted love of the Border regions”.

Royalties from the sale of Tweed Rins Tae The Ocean will be divided equally between the Western Isles Cancer Care Initiative and the Mamie Martin Fund, which supports the ­education of girls in Malawi.