Crater Lake

Crater Lake formed 7,700 years ago when Mount Mazama collapsed after a cataclysmic eruption, creating a caldera that filled with snowmelt and rain over thousands of years. With no rivers flowing in or out and exceptional clarity, the water reaches a blue so intense it seems artificial. At 1,943 feet it's the deepest lake in the US, and Wizard Island — a cinder cone — rises from its center.