The Lockwood–Mathews Mansion is a Second Empire style country house in Norwalk, Connecticut. Now a museum, it was built in 1864-68 for railroad and banking magnate LeGrand Lockwood. The 62-room 44,000 square feet (4,100 m2) mansion was listed on the National Register of Historic Places and was declared a National Historic Landmark in 1978. It has been described as "one of the earliest and finest surviving Second Empire style country houses ever built in the United States." It sits at 295 West Ave., in Mathews Park, where the Stepping Stones Museum for Children is also located.