The sheared, slaty rocks forming rugged scenery in this part of the Lake District were formed from ancient lava and volcanic ash (known geologically as the Borrowdale Volcanic Group). The stone is almost as hard as flint and was used by Stone Age man for axes and sharp implements, and is used everywhere today in roofs, walls, and dry stone walling defining boundaries, as well as offering shelter for hardy Herdwick sheep.
The first part of the route leads along quiet lanes towards Loughrigg Tarn, as attractive now as in 1810 when William Wordsworth described it in his Guide to the Lakes as “a most beautiful example of a miniature lake, a quiet and fertile domain, with a margin of green firm meadows, surrounded by rocky and barren steeps, overlooked by the solemn pikes of Langdale” (see my Loughrigg Tarn walk here).
On the uphill stretch to the lake, it is worth pausing to take in views to the south-west of the Old Man of Coniston, Wetherlam, Swirl How, and Grey Friar (see my walk here), with the jagged outline of the Langdale Pikes (see my walk here) standing out to the west. A lane leads down from the tarn to join the Langdale road at Skelwith Bridge (a two-span structure across the River Brathay, historically forming the boundary between Westmorland and Lancashire).
Just before Skelwith Bridge are the shop and workshop of the Kirkstone Slate Company. Attractive local green slate stone is made from volcanic ash laid down in thin layers that split easily, and has been sent worldwide for fireplaces, ornaments, and building facades.
Volcanic rocks are very resistant to erosion, and this bar of rock has formed Skelwith Force, where the River Brathay foams and cascades into deep greenish pools (especially impressive after rain in spate). Downstream, the Brathay flows gently over sand, silt, and clay into a saucer-shaped hollow scoured out of softer rock by glaciers, now filled with the still waters of Elter Water.
Elter Water is slowly shrinking as reeds colonise sediment on its fringes. The path goes through National Trust woodland (oak, ash, larch, birch, beech, willow, and alder), and returns on a well-maintained hard path parallel to Great Langdale Beck to Elterwater Bridge and the village.
Acknowledgment: Text derived from the Out and Out Series; Discovering the Countryside on Foot. Pictures courtesy of Wikipedia.