NBM Dive Site Resource
SM U-26
Western Gulf of Finland, Southern Finland offshore, Finland
A long-missing Baltic submarine identified by Finnish wreck divers in 2014. Documented discovery dives required a special permit and vessel-traffic coordination. Depth and precise location are not supplied here; arrange any proposed visit with the relevant authorities.
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Original NBM Artwork
Aquatic life at this dive site
What divers may encounter
Three reviewed connections are featured here. Sightings vary by season, conditions, and chance, so they are never guaranteed.
Aquatic life research in progress
NBM is reviewing a likely local species for this position.
Aquatic life research in progress
NBM is reviewing a likely local species for this position.
Aquatic life research in progress
NBM is reviewing a likely local species for this position.
Site media
Photographs
Three views rotate from the published gallery on each visit.
Contributor media
Dive videos
Three featured video positions are reserved on every profile.Regional location and nearby land
Location map
Regional overview includes nearby land for orientation. It does not establish a navigation waypoint or an entry location.Map data © OpenStreetMap contributors
Recent field observations
Diver-reported temperatures
Automatically checked observations from dives during the past 14 days. Three reports are visible at a time; scroll for more.A report that passes the automatic checks will appear here with the dive date, diver’s display name, and temperatures at each depth.
Reports are automatically checked for plausible dates, depths, and temperatures. They are observations, not forecasts; confirm conditions before diving.
Why divers know this place
Highlights
Exceptionally preserved early diesel submarine, partly embedded in seabed sediment.
Shipwreck-only module
The wreck
This section appears only on shipwreck records and brings the vessel, its loss, present condition, access, and responsible wreck-diving considerations into one place.
- Vessel type
- German Type U 23 submarine
- Year built
- 1913 (launched)
- Year sunk
- 1915
- Cause of loss
- Lost in late August 1915, attributed to a Russian minefield in the western Gulf of Finland.
- Present condition
- Exceptionally preserved early diesel submarine, partly embedded in seabed sediment.
- Penetration guidance
- External wreck context only. This record does not authorize penetration or artifact recovery.
Before you arrive
Access notes
Documented discovery dives required a special permit and vessel-traffic coordination. Depth and precise location are not supplied here; arrange any proposed visit with the relevant authorities. Confirm current access, restrictions, weather, tidal windows and support before planning a visit.
Plan within your training
Conditions and hazards
Major shipping lane, restricted operations, trawl netting, cold dark water and fragile military grave. Depth must be independently established before planning.
Independent resource notice
This record is a starting point for independent verification. Access, closures, moorings, weather, currents, depth, visibility, operator availability, and site conditions can change without notice. Confirm current information with the responsible operator, property owner, managing authority, or another qualified local source before planning or attempting a dive.