Derwent Isle is the only island on the lake that is inhabited; it is run by the National Trust and open to visitors five days a year.[71] The land between Keswick and the lake consists mainly of fields and areas of woodland, including Isthmus Wood, Cockshot Wood, Castlehead Wood and Horseclose and Great Wood, further to the south. The River Derwent flows from Derwentwater to Bassenthwaite, the most northerly of the major Cumbrian lakes.