The Kärnäkoski fortress is located on the Saimaa shore next to rapids that connects Saimaa and Kuolimo. It was built in 1791 as part of Russia’s outermost chain of fortifications against Sweden. The fortress was used to monitor water traffic between Lappeenranta and Savonlinna and road traffic along the Lappeenranta-Mikkeli road. There are fantastic views over labyrinthine Saimaa from the fortress.

No stone was excavated to build the fortress; instead, the boulders used were collected from nearby terrain. The stones include dark amphibolite, grey mica gneiss, tonalite and granodiorite, and are mostly rectangular. Some of the boulders are also roundish; these do not represent the local bedrock and were apparently glacially transported from a few kilometres away. Some of the fortress’ foundations have been restored by the National Board of Antiquities.

The fortification works of the Kärnäkoski fortress were organised by a famous Russian general, Aleksander Suvorov, who also managed the construction of four Suvorov canals named after him.

There is a Saimaa Geopark sign at the car park of fortress, which tells about the geology and history of the area: Contents of the Saimaa Geopark sign at Kärnäkoski fortress (pdf)

You can also find more information about the fortress here

Watch a video of the Kärnäkoski fortress on Saimaa Geopark’s YouTube channel.

To the south of the Partakoskentie road is a path to the smaller defence fortification known as the hill fortress. Along the way there is a lean-to shelter and the old barge harbour under the water of Lake Kuolimo.   You can find more information about the fortress path on the South Karelian Foundation for Recreation Areas’ website


When visiting Kärnäkoski, please note, to use parking areas. The road should be kept clear. Please also respect the boundaries of private areas. 

In summer, sheep work as gardeners in the fort, and bringing dogs into the fort is prohibited. Give the sheep possibility to full fill their task. 


Coordinates: x=538116,544 y=6792199,623 (ETRS-TM35FIN)

The above coordinates are working in GPS-devices and for example in service.

The below coordinates are working in Google maps service, which uses geographic coordinates:

Coordinates: 61.262194744, 27.710616237 (ETRS89 maantieteelliset(~WGS84))


Image: Arto Hämäläinen


  • Suitable for children
  • Melonta
  • Parking