“They guard it because they have hope. A faint and fading hope that one day it will flower. A King will come, and this city will be as it once was, before it fell into decay. The old wisdom borne out of the west was forsaken. Kings made tombs more splendid than the houses of the living, and counted the old names of their descent dearer than the names of their sons. Childless lords sat in aged halls musing on heraldry, or in high cold towers asking questions of the stars. And so the people of Gondor fell into run. The line of kings failed. The white tree withered. The rule of Gondor was given over to lesser men.” LOTR, Gandalf
