Complex sentence: A direct ascent of the fell seems to be impossible when it is viewed from the Stonethwaite valley, with vertical walls of crags seemingly barring the way, however a route can be found through the crags to attain the summit directly.
Split into simpler sentences: A direct ascent of the fell seems to be impossible when it is viewed from the Stonethwaite valley, with vertical walls of crags seemingly barring the way. However, a route can be found through the crags to attain the summit directly.