On Monday 30 August, a pair of Scottish walkers completed a route following what's thought to be the longest straight line in Britain without crossing a road.

For the whole 78km walk, from the A9 near Drumochter through the Cairngorms to the A939 near Corgarff, Calum Maclean and Jenny Graham stuck as closely as possible to a bearing of 67 degrees, taking in almost all the obstacles on the line. Thanks to the difficult path-less terrain, and the self-imposed rule not to stray off course unless absolutely necessary, the journey took them four days. 

High point of the route was the summit of Beinn a'Bhuird at 1197m, while the low point, figuratively, sounds like all the heather they had to plough through.

Jenny, a round-world record-breaking cyclist, said: "Walking in a straight line sounds like the simplest of all adventures but it turned out to be the most complex navigation of any trip I've been on."

"It's really tricky to stop yourself veering from the bearing on rough ground. You think you know what a straight line is but then you look at the GPS and realise you don't. We walked in a straight line for 11 hours and we covered just 10 miles on day one. They were the toughest 10 miles of my life. On day two, it took us 13 hours to do 13 miles. That's a mile an hour. It was so tough on all the heather and with so many steep ups and downs."

"You also have to let go of everything that is in your head. Sometimes this means not doing what appear to be the most sensible when looking at the terrain. However, completing the route and sticking as close to the line as possible... was pretty special."

The route was identified in 2018 by Ordnance Survey (OS) after a Twitter user asked about the longest distance it's possible to walk in a straight line in England, Wales and Scotland without crossing a road:

An OS cartographer determined the UK's winner was the A9/A939 route but commented, "I wouldn't recommend anyone do it unless they are very conversant with a map and compass. It is not following known tracks or paths and it looks like there may well be several scrambles along the way, too."

Other teams have tried, but it's thought that Graham and Maclean are the first to complete the wacky challenge. As backpacking routes go, it probably won't catch on; perhaps a line can now be drawn.

Adventure film production company Summit Fever Media intends to premiere a film about the journey at Kendal Mountain Festival this November.