It is said there is a wolf's lair on that mountain.
Tips
register
兽穴 is a written / literary term. In speech you'll more often hear specific dens: 狼窝 (láng wō, wolf's den), 狐狸洞 (húli dòng, fox burrow), or the general 巢穴 (cháoxué, lair / hideout — also used metaphorically of criminal hideouts).
