A Tico hidden gem, Cataractas Llanas de Cortes. It's not far off the Pan American Highway (gee whiz fact - Mrs. C and I are the only people we know who have been to both ends of the Pan American Highway) south of the provincial capital of Liberia but the turnoff is poorly marked and we drove past it. When Google Maps re-oriented us there were two or three kilometers of bumpy gravel road to the parking lot. We visited with a guide some years ago and the path down was very rough. There are new concrete stairs and a rope to hold, making it possible for my knees to make the climb.
When you get to the pool at the bottom you feel like you are well apart from the world. The escape doesn't last long enough.