An indulgence is granted the Christian faithful who devoutly visit a cemetery and pray, if only momentarily, for the dead.  This indulgence is applicable only to the souls in purgatory.  This indulgence is a plenary one from November 1 through November 8 and can be gained on each one of these days.  On the other days of the year this indulgence is a partial one.

"Thus he made atonement for the dead that they might be absolved from their sin."

(2 Maccabees 12:46)