Smith's Castle is a National Landmark built in 1678 near the trading center built by Roger Williams, the founder of Rhode Island, in 1636. Numerous archeological discovers have been made here, and in 1995 the original house underwent a major restoration. Costumed interpreters conduct guided tours of the grounds and house. Tours: Thur-Mon, noon-4pm, June-Aug; Fri-Sun, noon-4pm in May and September; by appointment rest of the year.