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Lighthouse Facts

A Beacon since 1901

Guiding Ships Safely Into Duluth

The Duluth Harbor South Breakwater Outer Light was established by the federal government in 1901 to mark the end of the Duluth Ship Canal’s South Pier. It replaced an earlier wooden tower built in 1874 and has served as a critical navigational aid ever since.

The Original Lens and Signal

A French Fresnel Lens and Early Fog Alerts

The lighthouse originally featured a fourth-order Fresnel Lens, crafted in Paris in 1877, visible up to 18 miles away. It also included an electric fog signal. Today, the Fresnel Lens is preserved at the Lake Superior Maritime Visitor Center, replaced by a modern LED beacon.

Structural Evolution

From Wood to Concrete

In 1885, a fog signal building was added just behind the wooden light tower. Eventually, all original wooden structures were demolished when Congress funded upgrades, transitioning the pier from timber to durable concrete for better stability and protection.

Changing Fog Signals

From Steam to Electric

The 1895 steam-powered fog signal was replaced in 1915 with two steam locomotive whistles. In 1923, a dual-horn Type “F” diaphone took over, powered by compressed air. Despite community resistance, the diaphone was permanently removed in 2006 and replaced with an electric foghorn.

No full-time keepers on site

Temporary Quarters Only

Though the station had space for overnight stays during storms, it never housed full-time keepers. Instead, keepers lived in two homes on Park Point—one built in 1873 for the head keeper and another in 1913 for assistant keepers and their families.

Unique Access and Forgotten Tunnel

From Piers to Pedal Power

Keepers typically walked the pier to reach the light. During poor weather, they used a pedal-powered rail car through a tunnel that ran from Park Point to the light station’s basement. By the 1950s, the tunnel was abandoned and filled in due to flooding.

Engineering the Foundation

Cribwork Beneath the Beacon

The lighthouse rests on a concrete base atop a massive timber crib filled with stone. This crib structure lies on the lakebed, 21 feet deep at the pier’s end—just outside the 27-foot-deep federally mandated shipping channel.

Lake Superior Marine Museum Assocation