National Park Mystery Photo 30: Kinda Sharp Looking, Ain't They?

What are these, and where in the National Park System can they be found?

What have we here, and in which unit of the National Park System were they photographed? Don't forget, there's often a story attached to every picture.

Comments

Folks, to my surprise, we've already got a winner. But we're gonna keep it under wraps to allow others an opportunity to test their parks knowledge.