Tailfin Pass Lake is situated in Tailfin Pass.The location is set through a mountain range similar to the Rockies. Mostly, it appears in the video games.
Tailfin Pass as seen in Cars: Mater-National Championship.
History
Cars
Lightning McQueen and Sally Carrera pass by a waterfall. Lightning looked at Sally in front of the waterfall,this is where the lake is situated.
Gallery
Sally Carrera in cars near the lake which is below the waterfall.
In the video-game.