Promontory point Utah is famous for?

The Golden Spike National Historic Site. This site marks the place where the first transcontinental railroad was completed in 1869. The Union Pacific Railroad from the east and the Central Pacific Railroad from the west met at Promontory Point, driving a golden spike to symbolize the completion of the railroad. This event was a major milestone in American history, as it connected the East and West coasts and made travel and transportation much easier.