where is promontory utah
Promontory, Utah. Promontory is an area of high ground in Box Elder County, Utah, 32 mi (51 km) west of Brigham City and 66 mi (106 km) northwest of Salt Lake City. Rising to an elevation of 4,902 feet (1,494 m) above sea level, it lies to the north of the Promontory Mountains and the Great Salt Lake.