A Glen is an area of the Penumbra saturated with the energies of the Wyld. Glens are usually tied to areas of unspoiled wilderness in the material world (making them increasingly rare and inaccessible). To Garou, a Glen is like paradise: not only are they surrounded by pure wilderness, they may study with nature spirits no longer found across the Gauntlet, and injuries heal rapidly and without scarring. Even Harano can be treated with time spent in a Glen.
The danger of such a paradise is that Garou may never want to leave it. Others fear it may lead them to over-idealize the Wyld, instead of striving to balance the Triat. However, to some Garou, a Glen is a badly-needed vision of hope in a world where the Wyrm and Weaver run amok.