The Haskell Free Library and Opera House (French: Bibliothèque et salle d’opéra Haskell) is a neoclassical building that straddles the international border in Rock Island (now part of Stanstead), Quebec and Derby Line, Vermont. The Opera House opened on June 7, 1904, and was deliberately built on the border between Canada and the United States. It was declared as heritage building by both countries in the 1970s.
Today, the library has two different entrances (one from each country), and hence, two different addresses: its American address is 93 Caswell Ave, while its Canadian address is 1, Church St. Exiting the library through the opposite entrance requires one to report to the country’s customs thereafter.
The library collection and the opera stage are located in Stanstead, but the main entrance and most opera seats are located in Derby Line. Because of this, the Haskell is sometimes called “the only library in the U.S.A. with no books” and “the only opera house in the U.S.A. with no stage”. Another entrance is accessible directly from Canada, and used to be a backdoor to the stage before, but reconstructed in 2013 in order to remain open to its Canadian visitors without the need to report to customs and immigration of either country.
A thick black line runs beneath the seats of the opera house and diagonally across the center of the library’s reading room to mark the international boundary. The stage and half of the seats are in Canada, the remainder of the opera hall is in the US.