What is your favorite day trip from Detroit to Canada?

I've met people from all over the country and for the vast majority of them, our proximity to another country, as familiar as it seems to us, is fascinating.

However I'm close with a newly minted Detroiter from the American heartland. She loves living in Detroit, but finds Windsor to be a pretty unappealing place and thus has based her entire opinion of Canada on Windsor. I'd like to show her that Canada can be at least mildly interesting, without having to go to Montreal or Toronto.

What would you recommend, outside of Windsor? No stories about Bob-lo. Let's let that one die.

Amherstburg is pretty quaint, the fort is a nice attraction, and a nearby bucolic getaway from the sprawling nature of Metro Detroit.

What else is there? Is London comparable to its namesake??