On a nice sunny day, the lighthouse foghorns were not needed but in inclement conditions like today, they were critical to the safety of ship crews before modern technology. The foghorns at Split Rock Lighthouse were first heard in 1910 at a 20 second interval in foggy conditions and could be heard roughly 5 miles away. The first ones were a siren-blast and after 1936 they were a type F diaphone. The foghorns went silent in 1961 as technology changed and reportedly as favor to a nearby resort owner. The Minnesota Historical Society took over the decommissioned lighthouse in 1976 and replica foghorns were placed atop the fog signal building in 1979 but the only sound heard now is a recording of the horn inside the building.
Split Rock Lighthouse Foghorns
