Translation:The interesting people in the Land of the Youth.
"The Land of the youth" is a strict literal translation of "tír na nóg", because of the way the genetive article works. For example, "the dog's food" is "bia an mhadra", literally "the food of the dog". To put it another way, the literal translation for "tír na nóg" is "the youth's country".
But because "tír na nóg" is a poetic, idiomatic, and literary phrase, we don't translate it literally. Grammatically, "The Land of the Youth" is correct. Idiomatically, is not.