Stanstead is a border town in Quebec's Eastern Townships, made up of Stanstead, Rock Island, and Beebe Plain. Its identity is unusually literal: the United States line cuts through streets, old houses, and the famous Haskell Free Library and Opera House. You do not come for a long list of sights. You come because the border has shaped the town in ways you can see on the pavement.
The Haskell Free Library and Opera House is the reason to stop. It was built to serve both sides of the line, with the border marked inside the building. Nearby, Colby-Curtis Museum fills a preserved granite villa with the story of an English-speaking border family, while Granit Central explains the grey granite industry that shaped local buildings and work.
Stanstead is small, but it has a stronger place identity than many larger towns. Check current border rules before visiting the Haskell, and do not treat Canusa Street as a casual crossing point. The oddness here is real, and so are the rules.