White Castle is a fast-food chain known for its small, square-shaped sliders. Founded in 1921, it is one of the oldest fast-food chains in the United States. White Castle is famous for its steamed burgers, which are cooked on a bed of onions. The chain has a cult following and is often associated with late-night cravings. White Castle has locations across the country and is a popular choice for those looking for a quick and affordable meal.