Analysis of information sources in references of the Wikipedia article "Nord Stream 1" in English language version.
In December 2006, Finland decided to join Nord Stream and to build a branch. ... The gas pipeline branch would go underground in the region of the Karelia isthmus, which, if necessary, would simplify the link-up with the Finnish gas pipeline system.
According to the Finnish natural gas company Gasum, a branch pipeline in Karelia connects the onshore section of the pipeline to Finland.