Line house

A line house is a building deliberately located so that an international boundary passes through it. The term is perhaps more frequently used in reference to the boundary between New England and eastern Canada than to other places. The most well known such building on the boundary between the United States and Canada is the Haskell Free Library and Opera House in Stanstead, Quebec and Derby Line, Vermont. The border is marked on the floor in a reading room and an auditorium. A number of single-family residences and some industrial buildings straddle the boundary in those two towns.

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