The Bonneville Salt Flats are located due west of both the Great Salt Lake
and Salt Lake City
. They are the remnant of a great lake created from glacier runoff long, long, ago
. As the water evaporated into the incredibly scorching heat, the salt content of the remaining water rose dramatically, leaving the Great Salt Lake
, a rank pond filled with salt to the point where lead can float (almost, it is pretty scary how buoyant you are) and the Bonneville Salt Flats
The proto-lake was called, of course, Lake Bonneville, and basically covered the entire valley floor. But enough geographical history.
The Salt Flats are compelling not just for the amount of freaking salt that Morton and Cargill salt pull from it, and send to the tables of millions of people, but for the fact it has become the place where you can find out just how fast you can go if you are both exceptionally stupid and have a very fast car, preferably with a rocket attached to it.
What people think of as the flats when they think of things like the land speed record, or the cars that have achieved great speeds on the flats, is actually thinking of a carefully measured, very straight path inscribed in the salt 80 feet wide and 10 miles long, with a black line inscribed down the middle of it and electronic timers for proper measurement of the speed of the cars attempting to go, well, really fast.
The Salt Flats are well suited for this kind of thing. They are hard, rigid and crystalline. Seen from the road, it is looks pure and white. Tires grab onto it quite well and it can handle extreme weights without cracking, which would be bad if you were going very, very fast
The plaque on the rest stop 7 miles north of the course (I-80 runs parallel to it) notes that due to the exceptional flatness of the course, you cannot see the end of it from the beginning due to the curvature of the earth.
The Blue Flame and the Spirit of America, both rocket powered, exceeded 600 and 800 MPH, respectively. Other notable cars include the hometown favorite, the Mormon Meteor (1931). People have raced Model Ts, there, and rumor has it that someone raced a truck trailing an Airstream trailer down it once. I can't confirm that. There is a lot of terrific info about the flats on the web, so go have fun.