Caves, Caverns and Subterranea

The caves and caverns of Valine hide secrets, and the dungeons and tunnel systems used to hide from the surface in times of trouble, disease or ecological disaster are a wide ranging feature of Valine, whether artificially constructed or naturally formed. Then there is The Undervale, a realm unto itself even deeper than most caverns are thought to be with horrors unimagined by surface dwellers and some of the most advanced societies on Valine hidden away from the surface world.