There are some railroads you visit for the scenery, such as the Skunk Train.  The Grand Canyon Railroad eventually ends up at the rim of the canyon, of the most astonishing sites you'll ever see.  Whether you go there by rail or car, don't leave the planet without seeing it at least once.  Between Williams and the Grand Canyon the landscape is punctuated primarily by clumps of grass and ant mounds. 

This landscape has beauty of its own.  It's a beauty better appreciated if the staff of the train would ever shut up.  They don't.  They drone on and on.  Buy this.  Buy that.  Another drink (sorry, we weren't talking to you homos...)