Forau de Aigualluts is a cool spot in the Province of Huesca, Spain, where you can check out a rad karst formation and waterfall. It's at a high altitude on Pico Aneto and the waters from the Aneto glacier disappear into a chasm here, only to pop up again in the Val d'Aran. The colorful Aiguallut waterfall adds a nice touch to the scenery, making it a must-see for anyone exploring the Benasque Valley for the first time. It's like nature's own magic trick!