 In the north Cumbrian plain, around the Carlisle area and into southern Scotland, evidence has been found for woodland clearance and deliberate fire-setting as a method of managing the landscape during the Mesolithic period.Large Mesolithic flint-chipping sites, where flints washed up from the Irish Sea were worked into tools, have been found at Eskmeals, near Ravenglass on the west coast, and at Walney in the south.At Williamson's Moss in the Eskmeals area, Bonsall discovered 34,000 pieces of worked flint (pebble flint), chert and tuff, plus wooden raft-like structures that suggest permanent or semi-permanent settlement by the wandering hunter-gatherer population.