WordNet (r) 3.0 (2006):

old times
    n 1: past times remembered with nostalgia [syn: auld langsyne,
         langsyne, old times, good old days]

Moby Thesaurus II by Grady Ward, 1.0:

19 Moby Thesaurus words for "old times":
   auld lang syne, days beyond recall, days of old, days of yore,
   early times, eld, good old times, lang syne, long ago, old days,
   old story, olden times, same old story, the olden time,
   times of old, times of yore, way back, yore, yoretime