Located in the caldera of the ancient volcano Mount Mazama, Crater Lake reaches down nearly 2,000 feet at its deepest point. It’s not only the deepest lake in the country, it’s also the 9th deepest lake in the world.

The first thing you’ll notice, however, is the vibrant blue color of the water. How could it be so blue?! Well, it’s actually because the water is so incredibly pure.

Sourced entirely from rainwater and snowmelt, this ancient lake is said to be one of the purest in the world (wikipedia). The unique combination of the lake’s depth and clarity allows for light to reach deep down into the water, and because there’s so little there to obstruct the light (like algae, dirt, or marine life), a bright blue color reflects back to our eyes, uninterrupted. It’s not that the water itself is blue (if you scooped it into a cup, it would be completely clear); it’s that the depth of the lake allows water molecules to absorb all of the other colors in the light, so that only blue reflects from it.

Here’s a photo of the big blue basin from above.

The lake is an amazing place for sightseeing and photography. It’s spectacular at any time of day; here’s a photo of the lake at sunset.

One great way to see the lake is by cruising along Rim Drive. Rim Drive is a scenic highway with tons of overlooks that circles the entire rim of the lake.

You can also stay the night at the wonderful Crater Lake Lodge, or bring a tent and camp at one of the nearby campgrounds.

While it’s mostly known as a sightseeing location, there’s actually one place (unbeknownst to many) where you can swim in the cold, clear water.

This amazing place is absolutely enchanting.