Hundreds of sled dog riders have gathered in the Highlands for Britain's biggest rally.

The 33rd annual Aviemore Sled Dog Rally is set to kick off at Loch Morlich in Glenmore on Thursday.

More than 1000 sled dogs will lead 250 mushers through forest trails in the shadow of the Cairngorms between January 21 and 26.

If there is no snow, the huskies, malamutes, Samoyeds and Canadian Eskimo dogs will pull their riders in three-wheeled buggies.

A spokesman for the Siberian Husky Club of Great Britain said: "From an original of only 12 teams, the race is now the largest event of its kind in the UK, with over 1000 sled dogs and 250 mushers.

"The race features teams of between two and eight dogs pulling their musher on a sled around a four to seven-mile trail.

"If there's no snow at ground level for the event, the races still go on with mushers using a three-wheeled rig that looks like a tricycle without a seat.

"There are eight adult classes and two children's classes and mushers range from just 8 years old to over 60."