A 27-mile road race set amid some of Scotland's most rugged terrain can no longer be classified as a marathon thanks to the poor condition of the course.

The Cape Wrath Challenge Marathon has attracted runners from around the world for more than a decade.

However, organisers have now been asked to rebrand the race as an "off-road event" because the track is too potholed to meet official marathon requirements.

Durness Active Health (DAH), which runs the event, said in a statement: "We recently requested Scottish Athletics to re-assess our measured courses, something we have to do periodically.

"It seems that their course measuring 'regime' has changed recently.

"Runners who have competed on the course will be aware of how poor the road surface is and Scottish Athletics have now advised us that the Cape Wrath Challenge Marathon course no longer qualifies as a marathon course due to its 'rough and broken running surface'.

"International Association of Athletics Federations requirements are for races to be held on sealed road surfaces.

"They have however issued a 'Statement of Course Measurement' confirming that the course is of marathon distance but should now be classified as an 'off-road event' and we do have a 'Race Permit' for the race."

DAH said it still expects the majority of runners who have booked places to take part in the event.

However, the reclassification could affect some runners who were relying upon their completion of the race to qualify them for entry to other marathons later in the season.

The Cape Wrath 10K and half marathon are not affected by the ruling.