How did the Arches form you ask?
Right here:
Role of fracture localization in arch formation at Arches National Park, Utah
Unweaving the joints in Entrada Sandstone, Arches National Park, Utah, U.S.A.
Development of natural sandstone arches in south-eastern Utah- Robert Blair (1987)
An animation of Arch formation within Arches National Park:
http://www.classzone.com/books/earth_science/terc/content/visualizations/es1601/es1601page01.cfm
This video attempts to show how the "monuments" of Monument Valley have formed:
Monument Formation ...Although I don't agree with it... As one of my professors once told me, "It has a lot more to do with down-dip cuesta scarp retreat." So, this animation is just a little too simple...but not bad.
My music choice for this road trip from Hwy 128, to Arches, to Canyonlands, to Monument Valley?
Mumford and Sons (never a bad choice!), 1, 2, 3
Trampled by Turtles, 1
Old Crow Medicine Show, 1
Avett Brothers, 1, 2