One of my submissions for Equestria Daily's 2014 "Ponies Around the World" event. This one has Pinkie Pie at the top of the highest dune, (470 feet,) at the Bruneau Dunes State Park in Idaho.
They say it's 470 feet, but it feels more like 1,000, because for every step up you take, you slide back down at least half a step. Pinkie didn't have to do any of the walking, though.
It was a good day for it, not too hot, but it sure was windy at the top. I had to wedge Pinkie in pretty deep to keep her from blowing away, and the sand flying through the air made it difficult to get a good shot. Sometimes I just had to stop, shut my eyes, and wait for it to die down.