Having been educated in the US Public School system, typing any letter that requires more than 2 keystrokes is beyond my abilities.
However, I should have gotten Botniabanan right since I cut and pasted it from a website.
(probably designed and maintained by another public school educated US resident)
I did find one .pdf that mentioned the tunnel, but, only noted that it was 1.1km. It may not be the right tunnel, but, the length seems about right.