The Tordenskiold Oak in Kjølhalskogen in Horten, Norway is one of the oldest trees in Norway. The tree trunk is very hollow, so the tree is almost split in two. The oak was protected by a royal decree on December 9, 1921. It is not possible to say how old the tree is, but it goes for at least 800, maybe close to 1,000 years. The tree has been supported and bolted to hold the trunk together, and a fence has been set up around the tree as a hedge on the day it falls.
The biggest threat to the tree was in 1993, when it was discussed both to lift the conservation and to have the heavily enclosed tree removed. Local environmental protection authorities were concerned about the safety, but lacked the financial means to take adequate security.
Wikipedia https://en.wikipedia.org/wiki/Tordenskiold_Oak
Official Website https://faktaark.naturbase.no/Vern?id=VV00002115
Address 46 Gamleveien, Horten 3189, Norway
Coordinates 59°25'57.347" N 10°27'14.963" E