I visited CRATER LAKE this summer (2012), one of Oregon's only national parks.
What I love about this lake its vastness (about 5 miles across in any direction), plus the water's BLUE COLOR. The color comes from the selective absorption and reflection of wavelengths (the blue wavelength is reflected, which is what the human eye sees).
What I think is creepy are the steep slopes, the depth (1,949 ft.) and the lake's somewhat inaccessibility, (although you can hike to the water, [about one mile down which allows one access to a boat tour]).
Below is an image of the lake's clarity. Moss even grows at the bottom of the lake because light is able reach it even at such depths.
Image source: makethebestofthings.blogspot.com
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