Fort Blunder: The Fort That America Mistakenly Built in Canada

During the American Revolutionary War and the War of 1812, between Great Britain and the United States, the border between British Canada and upstate New York saw some of the fiercest fighting, much of which took place around Lake Champlain. This freshwater lake situated across the US-Canada border provided the British a direct invasion route into the heart of America. Had this important travel corridor from the mighty Saint Lawrence to the Hudson fell into the hands of British troops, the results of the American Revolutionary War could have been very different. Anxious to prevent another invasion attempt, immediately following the War of 1812, America decided to fortify the shores of Lake Champlain. A small sandy spit called Island Point was chosen as the site for an octagonal fort. The fort, when finished, was to have 30-foot-high walls and 125 cannons that could blow out of waters any British ship attempting to sail past. Fort Montgomery, also known as Fort Blunder. Photo credit: Axel Drainville/Flickr Construction of the fort began in 1816, and continued for two years when a survey conducted jointly by the United States and Great Britain discovered a problem—the fort was being built on the wrong side of the border. The actual border passed almost a mile south of the fort. Once the embarrassing mistake was discovered, construction of the fort was hastily stopped and the unnamed citadel earned the nickname “Fort Blunder”. For the next 20 years, the abandoned fort was pilfered by local residents who carried away stones and building materials from it and used them to build their homes and public buildings. In 1842, American and British diplomats sat down to discuss this and many other boundary problems. The original border between New York and Quebec, as ratified by the 1783 Treaty of Paris, was supposed to pass along the 45th parallel, according to which Fort Blunder is on Canadian soil.