Walla Crag gives a superb view to what principal body of water in the Lake District National Park?
Walla Crag:  The fell is a popular short walk from Keswick and gives superb views over Derwentwater. Derwentwater: Derwentwater (or Derwent Water) is one of the principal bodies of water in the Lake District National Park in north west England.
Derwentwater