The Detroit River separates Windsor, Canada, from the U.S. by less than a mile. This was a funnel or sorts, with 75% of all smuggled Canadian liquor coming across the river. When the river froze in the winter, it was even easier–a car or truck could drive across or a man could pull a sled loaded with hooch. Of course, sometimes there were problems . . .
Canada also made drinking alcohol illegal, but the government shrewdly allowed its manufacture “for export only.” This industry brought lots of jobs and money to Canada.
In THE IMPERSONATOR (due to be published Fall 2013 by St. Martin’s/Minotaur), one of my characters smuggles liquor from Canada, but he does it in the Northwest, where Canadian Sam Bronfman, founded of Seagram’s, cornered the market on making booze and shipping it to America. Many smuggled it into the country over land; others came by sea. Part of the mystery is how my bootleggers got their liquor into Portland.
Mary Miley's Roaring Twenties 