Tower Hill State Park is a state park of Wisconsin, United States, which contains the reconstructed Helena Shot Tower. The original shot tower was completed in 1832 and manufactured lead shot until 1860. It was added to the National Register of Historic Places in 1973. The park abuts the Wisconsin River and is bordered by state-owned land comprising the Lower Wisconsin State Riverway.Natural historyThe bluffs along the Wisconsin River are formed of Jordan Sandstone. The park lies within the Driftless Area, a region of the American Midwest that remained ice-free through three successive ice ages. In the 19th century the Wisconsin River flowed directly past the base of the bluffs. The river has since shifted slightly, and a stream known as Mill Creek marks the northern boundary of the park.History of the shot towerShot towers harness the effects of surface tension on liquids in free-fall, a technique developed in 1782. Molten lead can be poured through a strainer at the top of a tower or shaft. The droplets become spherical as they fall and cool in this shape during their descent. The pellets are caught in a water basin to break their fall and finish cooling.In 1830 a businessman from Green Bay, Wisconsin, named Daniel Whitney was traveling along the Wisconsin River and recognized a sharp bluff near the town of Helena as a promising location for a shot tower. Lead deposits had recently been discovered in several locations around Iowa County. From the top of the bluff there was a 60ft sheer drop, below which the sandstone cliff sloped down to the riverbank, 180ft below the clifftop. Whitney formed the Wisconsin Shot Company with some other investors, and set his employee John Metcalf to oversee construction.
