Bonneville Salt Flats

The Bonneville Salt Flats are a 30,000-acre expanse of hard white salt crust in Tooele County in northwestern Utah, located approximately 110 miles west of Salt Lake City near the Nevada border. They are the remnant of Lake Bonneville, a massive prehistoric inland sea that covered much of the Great Basin roughly 15,000 years ago. The salt crust averages 5 feet thick at the center and creates a nearly perfectly flat surface that in summer becomes a crystalline white plain stretching to the horizon in all directions. The site is internationally known for land speed records; the Bonneville Speedway has hosted world record attempts since 1914, with notable records including Sir Malcolm Campbell's 1935 run of 301 mph and subsequent records exceeding 600 mph in streamlined vehicles. Speed Week, organized by the Southern California Timing Association, typically runs in August, while World of Speed (Bonneville Nationals) takes place in September; both events draw custom-built rocket cars, streamliners, and motorcycles competing for top speed records. Spectating at both events is free to the public from designated areas. Visitors can walk directly onto the salt surface from the I-80 rest area at mile marker 4 near Wendover year-round at no charge. In late summer the flats are typically dry and firm enough for vehicles to drive on with a free Bureau of Land Management permit. In spring and early summer, the flats often flood with a shallow reflective layer of brine water that creates a perfect mirror effect — one of Utah's most distinctive photographic subjects. The surface becomes extremely hot in summer midday, radiating heat upward from the salt; sunglasses and sunscreen are essential at all times.