The cast-iron frame watchtower predates the surrounding park's completion. Built in 1856 by Julius Kroehl, it occupies the highest point in the area. A watchman in the tower constantly looked out for fires and sounded the alarm by ringing an enormous bell. Samuel F. B. Morse's telegraph would eventually put such towers out of business. This tower, which ceased operations in the 1870s, is the only surviving watchtower in the city.