Along with the hut, the cave is the most primordial archetype of architecture. One is built, the other is dug; the first tends to be light, the second clings to gravity; the former is raised by joining pieces – it is tectonic – whereas the latter is shaped with the earth that is emerges from – it is stereotomic. These are parallelisms that issue 209 tackles through an essay by Dominique Perrault and five buildings excavated in the landscape, like the Tirpitz Bunker Museum (Denmark) by BIG, the Museum Fort Vechten (Netherlands), the Cava Arcari (Vicenza) by David Chipperfield, and the House-Restaurant crypt by Junya Ishigami in Yamaguchi (Japan).