Derby Line is a small town smack up against the Quebec border. It is unique in that the town’s Haskell Free Library and Opera House straddles the border between the U.S. and Canada. As shown in the picture at left, 40 percent of the building is in Vermont while 60 percent is in Stanstead, Quebec.
Source: http://haskellopera.com/
The library was deliberately built to straddle the border since the U.S. and Canadian towns are so connected. They share a water supply, a sewer system and emergency services, and, of course, a library. You can enter on the U.S. side, or you can enter in Canada, but you must leave by the same door you entered, or else register immediately at the nearest border crossing.
According to Canadian Geographic during the Vietnam War draft dodgers who fled to Canada would enter the library from the Canadian side and meet with family members who had entered from the American side. All was well as long as each stayed on their side of the room. Customs used to be more relaxed about such matters but after 9/11 the border was, and still is, monitored more intently. Source: http://www.canadiangeographic.ca/magazine/ja10/stanstead-border-town.asp
The building serves two purposes. The ground floor is a library while a performance hall is upstairs. As shown in the accompanying picture, a line is painted down the middle of the floor. Canada is on the right, the U.S. is on the left.
The upstairs part of the building has an equally odd arrangement. The performance takes place in Canada while much of the audience views from the U.S. side of the border.
Derby Line's Haskell Library is often touted as the ONLY building in the entire United States to straddle an international border but that is not true. Just down the road—to the west of Derby Line—is another border-straddling peculiarity. In the unincorporated village of Beebe Plain, Vermont, Canusa Street (short for Canada/USA) is the only road on the international border that sits right on the border. As shown on the map below, for the most part, houses on the south side of the street are in the United States while those in the north side are in Canada.
But when the road bends there is a border problem. A recent USA Today story form, June 2017 found a house for sale in Beebe Plain that also sits right on the border. The 7,000 square foot "Old Stone Store," which is quite dilapitated, is for sale for a mere $109,000. It has been on the market for some time and has no takers. Dealing with border post 911 is just as the own says "stresses everyone out."