In Irish mythology and folklore, Tír na nÓg (; "Land of the Young") or Tír na hÓige ("Land of Youth") is one of the names for the Otherworld, or perhaps for a part of it. It is depicted as a supernatural realm of everlasting youth, beauty, health, abundance and joy. Its inhabitants are the Tuath Dé, the gods of pre-Christian Ireland. In the echtrae (adventure) and immram (voyage) tales, various Irish mythical heroes visit Tír na nÓg after a voyage or an invitation from one of its residents. They reach it by entering ancient burial mounds or caves, or by going under water or across the sea.