It's not Lake Michigan

This is a picture of the lake out the back of my sister's door. It's
not very big (only three miles around) but it's also not very crowded.
The lake is called Crystal Lake because the water is crystal clear.
The lake is 160 feet deep at the deepest point and is fed by
underground springs.

If I'm not too lazy, I'll get out for my first run since the half
marathon!