Wasdale Mountain Rescue have had numerous call outs to people who have got in trouble on the screes above Wastwater and they've recently written an excellent web page analysing the incidents they've attended, not least to give people advice.
The Screes seen from across Wastwater
Most people seem to get stuck in the boulder field at the southern end and a compounding factor often seems to be a large dog who also gets stuck. Anyway have a read, it's well worth it, especially if you ever think you might go that way but more generally as a discussion of navigating scree slopes and boulder fields.
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