Wyoming 2011 - Bill Dreitlein
Morning Glory Pool in the Old Faithful area of Yellowstone National Park.  The different colors are caused by different strains of algae that thrive at different temperatures (all of them HOT).
Liz shot this picture while sitting on my shoulders.

Morning Glory Pool in the Old Faithful area of Yellowstone National Park. The different colors are caused by different strains of algae that thrive at different temperatures (all of them HOT).
Liz shot this picture while sitting on my shoulders.

Yellowstone NP