The gap gets its name from the whiskey that flowed through it and across the border during Prohibition. This was not just north to south as some might assume. Alberta had a prohibition period from 1914-1916, during which the whiskey rumbled north via wagons that traveled through the Gap. Even today the towns of southern Alberta directly north of us are all dry due to the influence of a large Mormon population. The nearest bar from our border crossing at Del Bonita is nearly an hour north.
Whiskey Gap was also the name of a thriving community on the north side of the Gap. These days it has been reduced to a single, one room church alongside the highway to Cardston. Back in 1976 it briefly came back to life as the setting for the film Days of Heaven.
Never heard of it? That's probably because it was a bomb. Sure had pretty scenery, though.