The number of national parks in Britain. 15 The depth of Lake Windermere - in metres. 66 The number of people who go on cruises on Lake Windermere - in millions. 1.35 The number of people who visit the Snowdonia National Park every year - in millions. 6 The length of the bay on the north coast of Wales - in kilometres. 3 https://339efcb25eb75e967b0d-ff8eeadd950d51fd1fc939dca75b3973.ssl.cf1.rackcdn.com/assets_green.swf