This classic Lake District mountain bike route starts and ends in Keswick and performs a full loop around the picturesque Derwent Water and Borrowdale valley. Despite being reasonably easy effort wise, the Borrowdale Bash includes several miles of wonderful technical singletrack and beautiful views across Keswick, Derwent Water, Skiddaw and the fells beyond.
As mentioned the route starts in Keswick (making it easy to access directly from the A66). The first leg takes the road south along the east bank of Derwent Water before climbing into the fells past Ashness Bridge and towards Watendlath Tarn. Birkett's Leap then drops you back into the Borrowdale valley and climbs the other side where it descends once again, flanking High Scawdel and returning north to Keswick via the Allerdale Ramble high above the west bank of Derwent Water.
You can start from anywhere in Keswick really. We chose the car park for the Theatre By The Lake because it's out of the way of the town centre, it's a pay and display car park but they all are as far as I know.
Exit the car park heading back to the roundabout. Turn right at the first roundabout and then right again at the second to get onto the Borrowdale road. As you follow this road south it's not long before you realise you're in the Lake District proper, as Lady's Rake and Falcon Crag rise up imposingly on your left whilst your right affords splendid views across Derwent Water with Cat Bells on its far bank.
After about 3km (2 miles) take the steep road on your left, signposted Ashness Bridge. This is the first of two road climbs on this route and it's a killer, but worth it. Ashness Bridge itself is the first must-stop photo opportunity. As you cross this ancient pack-horse bridge take a glance back towards Keswick and Skiddaw.
Beyond the bridge the slope becomes more gentle and eventually levels out as it passes a view point across Derwent Water and leads you to Watendlath Tarn. In the summer there's a tearoom here if you're looking for refreshments. This is also the end of the road and the start of the real mountain biking, cross either the ford or the footbridge on the right just before the tarn. The path soon forks, take the steep rocky right-hand track, which is the bridleway. This track quickly becomes a technical rocky climb which is fairly steep but fairly short.
The trail then levels out between Brund Fell and Yew Crag before dropping down again and turning into more technical riding only this time the right way round - downhill! Birkett's Leap has been described by some as the best bridleway in the Lakes, so make the most of it whilst also being on guard for stray walkers getting in the way. Where the path forks, keep to the left. The odd drop off and the plenty of drainage channels in this section make for an exciting descent into Rosthwaite.
Head towards the large hotel and car park and then the road beyond it. Turn left and follow the road along the Borrowdale valley and through Seatoller when the road quickly steepens and becomes Honister Pass, signalling the beginning of our second road climb. Just keep climbing now, because as painful as it might be, it'll be more than worth it. (Refreshments, a pub and public toilets are available in Seatoller.)
As you climb, keep an eye out on your right for an obvious gravel track that turns back on yourself and roughly follows the contours. Take this track. The next 2-3km (1-2 miles) of some more nice semi-technical riding with a few nice bridge crossings, and some excellent scenery. The track flanks High Scawdel before crossing Tongue Gill. From there you will join the Allerdale Ramble, flanking Low Scawdel, before descending down a stepped section and finally meeting the woods at Castle Crag.
Carry on down this loose rocky descent, which splits offering a few route options which all lead to the same place, perfect to have a little play about in the woods. As the bridleway once again levels out, keep with it heading towards Grange, another potential stop for refreshments from its cafe or shop. Take a left here and follow the road as it winds its way between fields and fells.
After about 1km (less than 1 mile), and just before the woodland on your left, take the bridleway on your left heading once again uphill. Follow it around the woods and take the right-hand fork when you come to it. Carry on around the woods and the trail flanks the well-known Cat Bells for about 2 miles before beginning to descend. Getting faster, this section quickly becomes quite exciting, just watch out for the odd water bar to hop.
This should spit you out once again on the road, cross the road where the bridleways continues for a short distance to the next road. Turn right here and follow the signs for final 5 miles to Keswick.