Just to look at it, Crater Lake and the MR location look similar. But it continues from there.
Due to several unique factors, most prominently that it has no inlets or tributaries, the waters of Crater Lake are some of the purest in terms of the absence of pollutants in North America.
Not to mention
The Klamath people also used Crater Lake in vision quests which often involved climbing the caldera walls and other dangerous tasks. Those who were successful in such quests were often regarded as having more spiritual powers
And it has an island in the middle (I've heard there's a lake in the island, but wiki doesn't say anything about it).