Loch Katrine, surrounded by peaks and woodland, is in the beautiful region of the Trossachs. This very long loch (16km) has served as a reservoir for Glasgow since 1859. To get a closer look, stroll or cycle down the lovely road alongside the north bank, or jump aboard the steamer Sir Walter Scott, a very pleasant way to explore the loch, made very popular by Walter Scott's poem The Lady of the Lake.