The inner sanctum of the temple was aligned so that the first rays of the sun on 21 February and 21 October would fall on the sacred barque deposited here and on the statues of four gods (Ptah, Amun, Ramses II, and Ra-Herekhty), though scholars are still not sure what was so propitious about these dates.
Scholars don't know why 21 February and 21 October were so important.