Built in 1895, the Sault Ste. Marie Canal completed an all-Canadian waterway linking the Atlantic Ocean to the interior of the continent. When it opened, the Canadian lock was the longest lock in the world and the first to operate using electricity. Electricity was produced in the powerhouse, one of the site's five beautiful historic buildings made of red sandstone excavated from the canal during its construction. The site is also home to the world's only remaining Emergency Swing Dam, which was built to protect the canal in case of an accident. After a lock wall failure in 1987, the canal was temporarily closed to vessels. In 1998, a smaller recreational lock was constructed inside the historic lock chamber, and the canal reopened to boat traffic. The recreational lock combines both historic and modern technology to operate.