IT'S the holy grail for hard core mountain bikers who enjoy a winter challenge.

And they don't come much tougher than the Strathpuffer.

Around 800 contestants are expected on the starting line tomorrow morning for the 24-hour endurance event involving gruelling laps of a route around Contin woods right through the night and often in sub-zero temperatures.

We thought we would share some photos from a previous year to help get everyone in the mood.

See also:

• Over 800 cyclists ready to huff and puff

• Strathpuffer participant targets 'silent killer' in mental health boost

• Get the Ross-shire's curated newsletter free to your inbox twice a wee

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Meanwhile, a snow and ice warning has been issued for Ross-shire this weekend.

The Met Office alert runs for 48 hours, covers the whole of Sunday and all of Monday, and was issued after forecasts predicted "frequent showers" across the north of Scotland.

Many of the event's converts relish the prospect of some snow and ice to contend with so, ironically, the weather warning may be greeted with a degree of warmth.

Updates on the event itself can be found on the event's social media page or its website.

The Puffer in a nutshell

The Strathpuffer - or "The 'Puffer" - started in 2005. It was meant to be a one-off local event, but somehow, more than a decade later it is a national event with a legendary status.

Event organisers say: "We now attract competitors from all over the world - probably because we were included in the US Bike magazines top 10 toughest Mountain Bike events on the planet - and we are widely recognised as the event every decent mountain biker needs on their palmares (record of achievements).

The Strathpuffer follows the traditional 24-hour MTB format with laps of a circa 12.5km course

It starts at 10am on Saturday morning and competitors must start their last lap by 10am on Sunday morning and complete it by 11am

The event is open to solos, pairs and teams of four.

There are two safety points on the course manned by marshals without whom the events would not be possible.

The event is timed by SPORTident which organisers describe as offering "bombproof accuracy and reliability".

They add: "To keep you smiling we have music playing throughout the event in the transition area - sometimes live, sometimes just good tunes."

Our photographer will be attending the event to capture images of some of the action. Stay tuned to our website for more on that.

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