The Longetivity of Hobbits.

[Belegorn]

In like manner the creations of the Ring and the Three that they built and maintained eventually went to waste. In Mordor the foundations were broken for good where they remained after Sauron's first overthrow since the Ring was not destroyed, and also the realms of the other 2 bearers of the Three.

Originally Posted by FotR; Bk. 2, Ch. 7; The Mirror of Galadriel

Do you see wherefore your coming is to us as the footstep of Doom? For if you fail, then we are laid bare to the enemy. Yet if you succeed, then our power is diminished, and Lothlórien will fade, and the tides of Time will sweep it away.