TinnsjåAbout Tinnsjå
Tinnsjø, often written Tinnsjå, is a large freshwater lake in Telemark in southern Norway. It is notable for its depth and for a significant World War II event involving the sinking of a ferry that carried industrial material.
The lake is used for regional transport, recreational boating and fishing, with shoreline towns providing ferry and road connections. The wartime sinking of a ferry carrying heavy water in 1944 is a key historical episode associated with the lake and draws historical interest.
Historically the lake and surrounding communities were tied to hydroelectric and industrial developments in the Rjukan area; wartime sabotage actions on the lake form an important part of local 20th century history.
Tinnsjø lies in the county area historically known as Telemark, with towns such as Rjukan on its shores; it is accessible by road from regional centres and forms part of the inland lake system of southern Norway.
- Depth and uses: The lake is among Norway’s deepest inland basins and is popular for fishing, boating and historical interest related to WWII events.
- Access: Rjukan and other local towns on the lake shore provide the main access points and visitor services for the area.
What to See#
- SF Hydro wreck: The wreck of the ferry SF Hydro, sunk in 1944 while carrying heavy water during World War II; the wreck lies on the lake bed and is a noted historical site.
Best Time to Visit Tinnsjå
For Tinnsjå, visit in summer (June-August) for the warmest weather and best conditions for lake activities.
Weather & Climate near Tinnsjå
Tinnsjå's climate is classified as Warm-Summer Continental - Warm-Summer Continental climate with mild summers (peaking in July) and freezing winters (coldest in January). Temperatures range from -9°C to 21°C. Moderate rainfall (652 mm/year).
| Month | Comfort | Temp | Feels | Rain | Sky | Humidity | Wind | UV | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | Poor | -8° - -2° | -7° | 44 mm | overcast | 97% | 1.4 m/s | 0.0 low | 6.7h |
| February | Poor | -9° - -1° | -7° | 28 mm | overcast | 97% | 1.5 m/s | 0.1 low | 9.0h |
| March | Poor | -5° - 3° | -3° | 38 mm | overcast | 96% | 1.8 m/s | 0.3 low | 11.6h |
| April | Poor | -1° - 8° | 2° | 28 mm | overcast | 89% | 1.9 m/s | 0.7 moderate | 14.3h |
| May | Acceptable | 3° - 15° | 8° | 48 mm | overcast | 80% | 2.0 m/s | 1.0 high | 16.8h |
| June | Good | 8° - 19° | 14° | 67 mm | overcast | 77% | 2.0 m/s | 1.4 high | 18.2h |
| July | Good | 10° - 21° | 16° | 77 mm | overcast | 80% | 1.8 m/s | 1.3 high | 17.5h |
| August | Good | 9° - 20° | 14° | 74 mm | overcast | 84% | 1.6 m/s | 0.9 moderate | 15.3h |
| September | Acceptable | 5° - 14° | 9° | 74 mm | overcast | 88% | 1.6 m/s | 0.5 low | 12.6h |
| October | Poor | 1° - 8° | 4° | 75 mm | overcast | 93% | 1.4 m/s | 0.1 low | 10.0h |
| November | Poor | -4° - 2° | -1° | 59 mm | overcast | 97% | 1.2 m/s | 0.0 low | 7.4h |
| December | Poor | -7° - -1° | -4° | 40 mm | overcast | 97% | 1.2 m/s | 0.0 low | 5.9h |
How to Get to Tinnsjå
Tinnsjå (Tinnsjø) lies in Telemark and is commonly accessed from the nearby towns of Rjukan and Notodden. By car it is reachable from Oslo in roughly 2.5-3.5 hours; follow main regional roads west from Oslo toward Notodden/Rjukan and then local roads to lakeside access points. Local regional buses serve Rjukan and Notodden from larger transport hubs, and short walks from roadside parking or bus stops lead to beaches, ferry points and viewpoints along the lake.
Tips for Visiting Tinnsjå
- Plan visits for late spring and summer (May-September) when roads and trails around Tinnsjå are open and daylight hours are long; winter ice and short days limit access and sightseeing.
- If you're interested in WWII history, arrange any technical dives to the SF Hydro wreck only through experienced cold-water operators - the wreck is historically significant but diving is deep, cold and regulated.
- Combine a lakeshore drive or ferry hop (seasonal services operate) with a visit to nearby Rjukan/Vemork for context; weekday mornings are generally quieter than summer weekend afternoons.