The steepest grade on U.S. main-line track is at the small town of Saluda, on a Norfolk Southern route between Spartanburg, South Carolina, and Asheville, North Carolina. The grade goes on for three miles at a slope of 4 or 5 percent. Trains have not been running on the line since 2001, but the tracks are still maintained.
For those who've never experienced a sunrise in the rural Midwest, it's roughly as soft and romantic as someone's abruptly hitting the lights in a dark room. This is because the land is so flat that there is nothing to impede or gradualize the sun's appearance. It's just all of a sudden there.
Robert Smithson and other so-called land artists simply disengaged from architecture, placing their works in America's open landscape, leaving behind the museums and galleries Smithson referred to as "tombs". A new "expanded field" allowed artists to contextualize their work beyond the institutional frame of the museum or the commercial structure of a gallery. Richard Serra, who also began to move outdoors, at times chose to "attack" architecture, creating structures that disrupted or overwhelmed the buildings around them.
The artists of the Light and Space movement took another tack. Rather than fight or flee the architecture, they explored and manipulated it, approaching architecture as a kind of found object, creating a series of rooms that incorporated architecture and architectural structures directly into their art. Bruce Nauman summarized it well: "When you work in a gallery or museum, the architecture is a given. If you wanted to have a show, you didn't have a choice, except to deal with it. You had to find a way to either absorb architecture into the piece of build your own."