Landmark Europe
Keri Lighthouse
Keri Lighthouse stands on a tiny rocky island in the sea near Estonia. Its light has helped ships find their way for about 300 years!
Keri Lighthouse stands on the small island of Keri in the Gulf of Finland, in Estonia. A light has guided sailors here since the early 1700s. Today's tower is a metal tower from 1858 set on top of an older stone base.
Keri Lighthouse, on the islet of Keri (Kokskär) in the Gulf of Finland, warns ships on the large shipping lanes around it. The Keri Society dates the lighthouse to 1719, while the Estonian Lighthouse Society says the first wooden lighthouse was completed in 1724. The present metal tower, made in St. Petersburg, replaced the wooden upper part in 1858.
Photo: Ivo Kruusamägi, CC BY-SA 3.0, via Wikimedia Commons
Discover Keri Lighthouse
Keri is a tiny island with no real trees, only stones and gravel.
The lighthouse stands on it to warn ships at sea.
Keri is one of the northernmost islands of Estonia, a little more than 3 nautical miles from the island of Prangli. The Keri Society says it is about 400 meters long and 80 meters wide, depending on the tide, and so small that no real trees grow on it.
The lighthouse helps ships find their way and warns them on the large shipping lanes around the island.
The island of Keri lies in the Gulf of Finland a little more than 3 nautical miles north of Prangli. The Keri Society describes it as mostly cobblestones and gravel, formed from rubble left by the last ice age, about 400 m long and 80 m wide.
The Estonian Lighthouse Society says the lighthouse helps navigation and warns ships on the large shipping lanes around the island. The Transport Administration maintains it, and lists it as light number 155.
- Where
- Keri island, Gulf of Finland, Estonia
- Island size
- About 400 m by 80 m
- Metal tower
- 1858
- Light number
- 155
From fire to lamps
Long, long ago, people lit fires on Keri to warn ships.
Later they built towers with lamps on top.
The Estonian Lighthouse Society says that in 1718 Peter I of Russia ordered a stone pillar on Keri on which a fire could be lit, and that the first wooden lighthouse was finished in 1724. The Keri Society dates the lighthouse to 1719.
In 1803 a wooden tower was built on a stone base, and its 16 lamps with copper mirrors were a first for Russia's lighthouses.
According to the Estonian Lighthouse Society, Peter I ordered a 30-50-foot stone pillar topped by a fire in 1718, and the first wooden lighthouse was completed in 1724; the Keri Society says Peter the Great established the lighthouse in 1719. Work on a stone tower began in 1800.
In 1803 an eight-story wooden tower was built on the stone part, and its lantern became the first in the Russian Empire fitted with reflector lighting: 16 lamps with copper reflectors made in St. Petersburg.
A metal tower on a stone base
The top of the lighthouse is a metal tower.
It stands on a wide stone base, like a cup on a big round drum!
In 1858 the old wooden top was replaced by a metal tower made in St. Petersburg from ready-made metal sheets, set on a cone-shaped stone base. Its new light, made in Paris, could be seen 12 miles away.
The Estonian Lighthouse Society says the lighthouse was 31 meters tall and painted dark brown, with a green roof on the lantern room.
In 1858 the wooden part was replaced by a prefabricated sheet-metal tower made in St. Petersburg, on a conical stone base. It received a dioptric lens apparatus from Henry LePaute's factory in Paris; the light stood 32 m above sea level and was visible for 12 miles.
The 31-meter lighthouse was painted dark brown with a green lantern roof. It switched to kerosene in 1876, and around 1895 a large fog bell was mounted on the roof of the stone section.
Gas from under the island
Long ago, this lighthouse used gas from under the island to make its light!
Today its light works by itself, using power from the sun and wind.
The Keri Society says gas forms under the island's clay as old plant material breaks down. From 1907 to 1912, the Estonian Lighthouse Society says, Keri was the only lighthouse in the world powered by natural gas from its own ground.
In 1995 the light was made automatic, running on solar and wind energy.
Beneath Keri's tight layer of clay, decomposing organic matter produces gas, the Keri Society explains. The Estonian Lighthouse Society calls it remarkable that between 1907 and 1912 Keri was the only lighthouse in the world powered by natural gas from the same ground.
In the 1930s a 4-meter-high reinforced concrete wall was built around the stone part to stop its outer wall collapsing, and in 1995 the light was converted to an automatic system powered by solar and wind energy.
- First reflector lamps
- 1803
- Natural gas light
- 1907-1912
- Automatic, solar and wind power
- 1995
- Light height above the sea (1858)
- 32 m
On the stony shore
This photo shows the dark red lighthouse on its wide stone base.
In front there is a beach of round stones and the sea.
Ivo Kruusamägi took this photo in 2007. It shows the dark red metal tower with its lantern and railings, solar panels on its side, the wide stone base, houses with rusty roofs, a long wooden shed, and a shore of round stones by the water.
Estonia protects the lighthouse as a national cultural monument.
The photo (Ivo Kruusamägi, 2007) shows the reddish-brown metal tower with its lantern and two galleries, solar panels, the broad stone base, low houses with rusty roofs, a timber shed and the cobble shore.
The lighthouse is a nationally protected cultural monument, and the Estonian Lighthouse Society says it is on the International Association of Marine Aids to Navigation and Lighthouse Authorities' (IALA) list of 100 lighthouse architectural monuments.
Amazing facts
-
This lighthouse once used gas from under its own island!
From 1907 to 1912, Keri's light ran on natural gas from the island's own ground.
The Estonian Lighthouse Society says that between 1907 and 1912 Keri was the only lighthouse in the world powered by natural gas from the same ground.
-
The island is so small that no real trees grow on it!
Keri is about 400 meters long and 80 meters wide, and too small for real trees.
The Keri Society gives the island as about 400 m long and 80 m wide, depending on the tide, with no real trees.
-
In 1803 the light had 16 lamps with shiny copper mirrors!
In 1803 Keri's lantern got 16 lamps with copper reflectors, a first for Russia's lighthouses.
Keri's 1803 lantern was the first in Tsarist Russia fitted with catoptric lighting: 16 lamps with copper reflectors.
Words to know
- lighthouse
- a tower with a bright light that guides ships and warns them of danger
- lantern room
- the glass room at the top of a lighthouse that holds the light
- reflector
- a shiny curved mirror that sends light out in one direction
- gulf
- a large area of sea partly surrounded by land
- natural gas
- a gas found underground that can be burned for heat and light
- nautical mile
- a unit used at sea, a little longer than an ordinary mile
Discovery challenge
-
In which sea area is Keri island?
In which body of water does Keri island lie?
Keri lies a little more than 3 nautical miles north of Prangli, in which body of water?
- The Gulf of Finland
- The Gulf of Mexico
- The Red Sea
Show the answer
The Gulf of Finland
The Gulf of Finland!
The Gulf of Finland, off Estonia.
The Gulf of Finland.
-
In which year did the metal tower go up?
In which year was the wooden top replaced by a metal tower?
In which year was the prefabricated sheet-metal tower set on the stone base?
- 1858
- 1995
- 1724
Show the answer
1858
In 1858!
In 1858.
1858.
-
What special fuel did the light use from 1907 to 1912?
What powered Keri's light from 1907 to 1912?
Between 1907 and 1912, what made Keri unusual among the world's lighthouses?
- Gas from under the island
- Coal from a ship
- Candles
Show the answer
Gas from under the island
Gas from under the island!
Natural gas from the island's own ground.
It ran on natural gas from the island's own ground.
-
What powers the light today?
Since 1995, what kinds of energy power Keri's automatic light?
Which energy sources power the automatic system installed in 1995?
- Sun and wind
- Wood fires
- Whale oil
Show the answer
Sun and wind
The sun and the wind!
Solar and wind energy.
Solar and wind energy.
-
About how long is Keri island?
About how long is the island of Keri?
About how long does the Keri Society say the island is?
- About 400 meters
- About 40 kilometers
- About 4 meters
Show the answer
About 400 meters
About 400 meters!
About 400 meters (and 80 meters wide).
About 400 m long and 80 m wide, depending on the water level.
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For parents & teachers
What children will learn
- Explain what a lighthouse does and why it is placed on an island.
- Describe how lighthouse lights changed from fires to automatic solar power.
- Explain how a reflector makes a light easier to see from far away.
Recommended ages: 4 to 17 · About 15 minutes
Talk about it
- Why would a tiny island in a busy sea need a lighthouse?
- Why do you think people stopped living at many lighthouses?
- What are the good and hard things about using sun and wind for power far out at sea?
Try at home or in class
- Shine a flashlight at a wall, then hold a shiny spoon or foil-lined cup behind the bulb and see how the beam changes.
- Find Estonia, Finland and the Gulf of Finland on a map, and mark where Keri might be.
Key vocabulary: lighthouse, lantern room, reflector, gulf, natural gas, nautical mile
Where these facts come from
- Wikidata , Wikimedia Foundation (CC0 1.0)
- Keri lighthouse , Eesti Tuletornide Selts (Estonian Lighthouse Society)
- Keri Island , MTÜ Keri Selts (Keri Society)
- Külastajatele avatud tuletornid (open lighthouses) , Transpordiamet (Estonian Transport Administration)
- File:Keri tuletorn.JPG , Wikimedia Commons
- Wikimedia Commons , Wikimedia Foundation (Per file (public domain, CC0, CC BY or CC BY-SA); see each media record)
Checked, not yet human-reviewed. Last updated November 1, 2026. Spotted a mistake? Tell us.