There are older and fouler things than Orcs in the deep places of the world. The Fellowship of the Ring, II, 4: A Journey in the Dark; said by Gandalf. Orcs will often pursue foes for many leagues into the plain, if they have a fallen captain to avenge. The Fellowship of the Ring, II, 6: LothlÃ³rien; said by Gimli. You must dig swift and deep, if you wish to hide from Orcs.