The northwest corner stave of the Urnes church in Norway.You can see how the stave rests on, and wraps over the wall sills which meet beneath it. To the right, you can see the protruding foundation sill – part of the foundation framework on which the entire building rests. You can also see how the wood is covered with tar, which has been used as a preservative for millennia. Image from the book “Världsarv i Norden” by Leif Anker and Ingalill Snitt.