Poll na bPéist is a hidden gem hidden in the Aran Islands of Ireland. It is suspected to be "the serpent's lair" and it looks like it was cut by machine, yet it was naturally formed. It contains multiple underground channels that are connected to the ocean. A visit here provides great views and can get busy during summertime. Plus, its nearby location to Dún Aonghasa fort gives travelers an opportunity to visit two popular landmarks in one trip. Swimming is not recommended in this area as the currents can be strong and unpredictable.