Shoreline · Lights
The Lights of the Inland Seas
235 lighthouses on the American shore of six lakes. Where each one stands, when it was built, how high the light sits, and the pattern it flashes — the one thing that tells a navigator which light is which.
Lighthouses
235
National Register
164
Earliest on record
1818
States
8
Light on record as in service Deactivated
By lake
Pick your shore
Lake Superior Lighthouses
Earliest on record: Copper Harbor Light, established 1848.
Lake Michigan Lighthouses
Earliest on record: Pottawatomie Light, established 1836.
Lake Huron Lighthouses
Earliest on record: Fort Gratiot Light, established 1825.
Lake Erie Lighthouses
Earliest on record: Erie Land Light, established 1818.
Lake Ontario Lighthouses
Earliest on record: Galloo Island Light, established 1820.
Lake St. Clair Lighthouses
Earliest on record: Windmill Point Light, established 1838.
By state
Field skill
How to read a light
Every working light shows a pattern of its own, called its characteristic, so that from offshore at night you can tell one harbor from the next. The Coast Guard Light List writes it in shorthand: the pattern, the color, then the period — the seconds it takes to run through one full cycle.
Fl W 6s is one white flash every six seconds. Fl(2) W 20s is two white flashes, repeated every twenty. F R is a steady red light that never blinks. Count the seconds between the start of one cycle and the next with a watch, not in your head; everyone counts fast in the dark.
Color carries meaning at harbor mouths. Under the U.S. lateral system, coming in from the lake you keep red marks on your right and green on your left — red, right, returning. That is why so many pierhead lights on this directory are red or green rather than white.
Focal height is how high the lamp sits above the water, and range is how far it carries in clear weather, in nautical miles. A tall light on a bluff shows over the horizon long before a pierhead light does.
| Shorthand | What you see |
|---|---|
| Fl W 6s | One white flash every 6 seconds.23 lights, e.g. Lorain East Breakwater Light |
| Iso W 6s | A white light, on and off in equal halves of a 6-second cycle.15 lights, e.g. Fairport Harbor West Breakwater Light |
| F W | A fixed white light, on all night without flashing.11 lights, e.g. Buffalo Main Light |
| Oc W 4s | A white light that goes dark briefly once every 4 seconds.3 lights, e.g. Fourteen Foot Shoal Light |
| Fl(2) W 20s | A group of 2 white flashes, repeated every 20 seconds.3 lights, e.g. Pointe Aux Barques Light |
Characteristics change when lights are relit or re-lensed. On the water, use the currentUSCG Light List, Volume VII.
About this directory
How many lighthouses are on the Great Lakes?
This directory lists 235 on the U.S. shore with a public record of their own: towers, pierhead and breakwater lights, and range lights. Counts elsewhere vary with what gets counted — minor aids, Canadian lights, and lights on the connecting rivers. Michigan has the most of any state.
Where does this lighthouse data come from?
From Wikidata, the open structured-data project behind Wikipedia, which records coordinates, dates, heights, light characteristics and National Register listings for each light. We publish only what the record holds and link each page to its source. Retrieved 2026-10-09.
Are Great Lakes lighthouses still working?
Many are, automated and maintained by the Coast Guard, while the buildings around them have often passed to parks, museums and local societies. Where a light has been deactivated, its page says when. For a light’s current status on the water, the USCG Light List is the authority.
Can I navigate by these charts?
No. The shorelines are generalized for illustration. Use a current NOAA chart, the USCG Light List and a chartplotter on the water.
Lighthouse data: Wikidata (CC0), retrieved 2026-10-09. National Register references: NPS NPGallery. Shoreline: Natural Earth 1:10m lakes (public domain). Corrections to contact@greatamericanlakes.com.