Today in 1926, Grand River Avenue, or Historic US-16, opened in Michigan, becoming the first paved road to stretch completely across the state. Connecting Detroit to Muskegon, it served as a primary highway for nearly four decades. Today is also National Lighthouse Day. Michigan boasts around 115 lighthouses, the most of any U.S. state. Built between 1818 and 1822, these lighthouses guided ships safely through the Great Lakes.