Marquette Harbor Light has guided vessels on Lake Superior toward Marquette’s ore docks since the 1850s, reflecting the port’s importance and the lake’s harsh conditions. Congress funded the first light in 1850, but that structure deteriorated quickly, and the present lighthouse grew out of rebuilding begun after 1865. Its design combines a tower and keeper’s dwelling, while repeated changes to lenses, fog signals, electrification, and harbor works show continual adaptation to wind, waves, and fog. The site later became part of broader federal maritime services, including the Life-Saving Service and Coast Guard, served as a World War II training station, and remains an active navigational aid.