Oranjestad’s oldest building was constructed in 1798 as a Dutch fortress. At its base are two of the original canons. The Willem III Tower, named after the King of the Netherlands (1849-1890), was added to Fort Zoutman in 1868. It functioned as a lighthouse for almost 100 years. After an extensive renovation, the old citadel became the Historical Museum of Aruba in 1984.