(S)The walk starts from the car park at the foot of the Hardknott Pass and follows a path roughly south west in parallel to the main valley. It starts easily enough and then leads gradually upwards along the side of the lower reaches of Harter Fell with views of the Eskdale valley opening up below to the right with the Scafell range in the background. After the path contours Harter Fell in a south to south east direction for about half a mile without any noticeable height gain, it suddenly branches off to the left and takes a "route one" approach to the top. This is the one really steep section that is likely to increase your heart rate before long as the route climbs somewhat unrelentingly up the grassy felllside. It is not until it nearly reaches the upper reaches of the mountain that the gradient eases off.
(1)The summit area, which has a trig point to mark the very top, is notable for its outcrops of clusters of rocks which offer scrambling opportunities. The author takes the view that tarns, as well as summits, are worthwhile walk objectives and therefore the return route takes in Low Birker Tarn, rather than repeating the outgoing route in reverse. Walk back down the steep path to the junction with the path from Eskdale which you then follow for about a quarter of a mile before leaving the path and walking across pathless ground between Dow Crag and Kepple Crag to reach the tarn.
(2)Low Birker Tarn is one of the prettier, but less well-known, tarns in the Lake District. Choose a sunny day, and it may appear as a royal blue colour. Through the crystal clear waters of the tarn, in places, submerged tree roots can be seen. Green Crag provides a good backdrop to a photo of the tarn as well as offering an alternative area to explore on the return route.
(3)A clear path leads down back to Eskdale, zig-zagging in places to Low Birker Farm and then back along a path to the east by Penny Hill Farm to rejoin the car park.