Alaska’s Inside Passage
Mary Island Light: A Beacon on the Southern Approach
At the entrance to Revillagigedo Channel, Mary Island Light helped guide vessels toward Ketchikan and the waters of Southeast Alaska. Explore the island’s setting, the station’s history, and its place in coastal navigation.
A Strategic Island
Mary Island sits near the Alaska–British Columbia border, along a busy route into Southeast Alaska.
An Enduring Aid
Though the original station has changed, a navigational light continues to mark these waters.
Where Coastal Routes Meet Open Water
Mary Island lies in Southeast Alaska, south of Ketchikan and near the Canadian border. It stands by the southern entrance to Revillagigedo Channel, a passage used by vessels traveling between the Inside Passage and communities along Alaska’s coast. Islands, channels, weather, and tides make this a demanding place to navigate. Established here in the early twentieth century, Mary Island Light served mariners approaching the region from the south and became part of the network of aids that supported Alaska’s maritime traffic.
A History Marked by Change
These milestones separate documented station dates from the broader developments that shaped navigation at Mary Island.
1903
Station Established
Mary Island Light Station was established to mark the approach to Revillagigedo Channel and help vessels bound for Southeast Alaska.
1903
First Light Exhibited
The original light began service in 1903, giving mariners a fixed reference point near the southern approach to Ketchikan.
1937
Station Rebuilt
A replacement lighthouse was built in 1937 as the station’s facilities changed over time.
20th century
Navigation Evolves
Improved charts, communications, and vessel equipment changed how mariners used coastal lights, while the marked approach remained important.
20th century
Light Automated
The light was eventually automated, ending the need for a resident crew to operate it; the exact changeover date is not stated here.
Today
A Continuing Maritime Landmark
A modern aid to navigation marks Mary Island, preserving the site’s role in guiding traffic through Southeast Alaska’s coastal waters.
A Light on Mary Island
Mary Island Light was established in 1903 near the southern entrance to Revillagigedo Channel in Southeast Alaska. Its first station paired a light with a fog signal, giving vessels two ways to locate the island in the region’s frequent low visibility.
Built for an Exposed Coast
The original station included a wooden lighthouse and keepers’ buildings. Set on an island off the coast near Ketchikan, the light marked a prominent point along the route between the Inside Passage and the open waters to the south.
From Keepers to Automation
Mary Island’s buildings and equipment changed as navigation technology advanced. The station was automated in 1969, ending the need for resident keepers; its historic lighthouse was later replaced by a modern light structure. The site continues to serve as an active aid to navigation.
How Mary Island Light Guided Mariners
Marking Revillagigedo Channel
The light helped vessels recognize the southern approach to Revillagigedo Channel, an important waterway leading toward Ketchikan.
Identifying the Island
Its position made Mary Island easier to distinguish from the surrounding shoreline as ships navigated Southeast Alaska’s intricate coastal waters.
Guidance in Poor Visibility
A fog signal supplemented the light when mist or darkness obscured the coast, helping crews judge their position near the channel entrance.
Supporting a Busy Passage
For vessels moving between the Inside Passage and waters farther south, the station provided a dependable reference point on a consequential stretch of route.
“The lights are lit at sunset and extinguished at sunrise.”
U.S. Lighthouse Board, Instructions to Light-Keepers—a reminder of the daily watch that defined stations such as Mary Island before automation.
Mary Island Light and Alaska’s Coastal Lifelines
Near the southern end of the Inside Passage, Mary Island Light helped mariners navigate the waters around Revillagigedo Island and the approaches to Ketchikan. As shipping, fishing, and passenger travel expanded in southeastern Alaska, dependable coastal lights gave crews recognizable points of reference along a shoreline shaped by islands, narrow channels, and changing weather. Mary Island became part of a wider network of aids to navigation that made these working routes easier to follow.
That network supported more than passing vessels. Fishing crews, freight carriers, mail boats, and travelers moving between coastal communities all depended on navigable waterways. Mary Island’s story links the practical work of keeping a light to Alaska’s broader maritime development, while changes to its equipment and operation reflect the evolving ways navigational aids have served the region.
Explore Public Records and Maritime Collections
Follow the Lights Beyond Mary Island
Mary Island is one stop in Alaska’s coastal story. Continue to Point Retreat and discover how another lighthouse served mariners on a different stretch of the state’s waterways, then explore more light structures across Alaska Lighthouses.