Grinnell lake is found in Glacier National Park along the Grinnell Glacier Trail. It is fed by Grinnell Creek which arises from the Grinnell Glacier on Mt. Grinnell. Wondering who it’s named after…George Bird Grinnell! The lake has an opaque, turquoise appearance from the rock flour (silt) which is transported to the lake from Grinnell Glacier. Angel wing is seen in the background. Photo © copyright by Dr. Edward Mikol.