Storsjöodjuret — Cryptid Encyclopedia

On a rune stone near the church of Frösön in Jämtland, Sweden — dating to approximately 1000 AD — a serpentine creature is depicted, bound by a runic inscription. Some researchers believe this stone represents the earliest reference to the creature that inhabits Lake Storsjön, known as Storsjöodjuret — "The Great Lake Monster."

The first written account dates to 1635, when the vicar of Herdal parish recorded a description of a long-bodied creature with a dog-like head, smooth dark skin, and multiple humps seen moving through the lake's waters. Since then, over 500 sightings have been documented — making Storsjöodjuret one of the most frequently seen lake cryptids in the world.

The creature is typically described as approximately 33 feet long, with a serpentine body, a cat- or dog-like head, dark grayish-brown skin, prominent eyes, and visible humps or undulations when it surfaces. It moves rapidly through the water and is most often seen on calm summer evenings.

In 1894, a trapping company was formed with the explicit purpose of capturing the monster. Harpoons and nets were deployed. The creature was never caught, but the attempt demonstrated how seriously the local population took its existence. In 1986, the Swedish government officially classified Storsjöodjuret as an endangered species, providing it with legal protection — a status that was later revoked in 2005.

"It was long and dark, with a head like a dog. It moved through the water in great undulations, leaving a wide wake behind it." — A fisherman's account from the late 19th century.

Lake Storsjön is the fifth-largest lake in Sweden, reaching depths of nearly 250 feet, with cold, dark water and a surface area of 176 square miles. Sonar surveys have occasionally detected large, unidentified moving objects in the depths. Whatever lives in Lake Storsjön, it has been there for at least a thousand years — if the rune stone is to be believed.