If you hang around Park City long enough, you will come across things with the name Ontario. There's Ontario Avenue. There's the Ontario hiking trail at Deer Valley. And I'm sure there are other things.
As a Canadian, I couldn't help but wonder why. So today I looked it up. And it turns out that the mining company that first put Park City on the map was the Ontario Silver Mining Company (see above stock certificate).
Established in 1872, it was a major contributor to Park City's economy (when it was a mining town) and it is usually credited as the mine that generated the most consistent yield in Utah during the late 19th century.
Cool, so why was it called Ontario? Well, according to the Park City Museum, the mine was first discovered by prospectors from Canada (though they later sold off their claim to George Hearst for a handsome $30,000).
I can't seem to find any info about these Canadians, but the province of Ontario did get its name in 1867, so at least the chronology check outs.
Image: Park City Museum