Mr. Chilian said in an E-mail: "attached is a map showing our trip. We started in Denver drove up north to Mt. Rushmore, than west to Yellowstone NP, south to Salt Lake City to Grand Canyon. From there we drove east along all the canyons back to Denver."

Note: Bad Lands NP

Badlands are a type of arid terrain where softer sedimentary rocks and clay-rich soils have been extensively eroded by wind and water. It can resemble malpaís, a terrain of volcanic rocks. Canyons, ravines, gullies, hoodoos and other such geological forms are common in badlands. They are often difficult to navigate by foot. Badlands often have a spectacular colour display that alternates from dark black/blue coal stria to bright clays to red scoria.

Features
The term "badlands" represents a consensus in North America: the Lakota called the topography "Makhó?i?a", literally bad land, while French trappers called it "les mauvaises terres à traverser" – "the bad lands to cross". The Spanish called it tierra baldía ("waste land") and cárcava. The term badlands is also apt: badlands contain steep slopes, loose dry soil, slick clay, and deep sand, all of which impede travel and other uses. Badlands form in arid regions with infrequent but intense rain-showers, sparse vegetation, and soft sediments: a recipe for massive erosion.

Some of the most famous fossil beds are found in badlands, where erosion rapidly exposes the sedimentary layers and the scant cover of vegetation makes surveying and fossil hunting relatively easy.(See here)