Kalso Serenity Negative Heel Earth leather Studded Sandal Danish Inspired by yoga and deeply rooted in the belief that wellness starts from the ground, our signature negative heel designs are still inspired by the mountain pose - just as originally created by Danish yoga instructor. In the early 1970’s, Kalsø shoes took the world by storm with colors that hit all the vintage notes, and the gently inclined sole that keeps you feeling great.