The Ayai'leh-hirh range is the largest mountain range on the planet Trill, and one of the largest on any inhabited planet known to Federation scientists as of the 2370s. In English, the name of the range translates to Five Thousand Valleys.

Mountains in the range include Arken, Ilrienh, Noraikghe, Oraidhe, and Sethe. (TNG novel: Intellivore)

the planet Trillius Prime
cities and settlements	B'tar • Chi'tar • Gheryzan • Iklan • Kural • Leran Manev • Mak'ala • Murona • Shator • Tear'c • Vor'lan • Vrans
landmarks and geography	Ayai'leh-hirh (Mount Arken • Ilrienh • Noraikghe • Oraidhe • Sethe) • Caves of Mak'ala • Deln Mountains • Devritane Museum • Dorabi subcontinent • Dorvan mines • Ganses Peninsula • Hoobishan Baths • Irnek Peninsula • Kem'alta Institute • Korchub Mountains • Lekarna Mountains • Manevri • Najana Library • Nalep Mountains • Tash Mountains • Tenar • Tenara (Tenaran Ice Cliffs • Tenaran Music Academy) • Thorain Mountains • Trill Senate Tower • Urot Mountains • Venar Mountains
bodies of water	Aldar Bay • Dara'air Ocean • Lake Ograls • Manev Bay • Sea of Arlibath • Troyval Ocean • Turek Sea • Uzonn Ocean