Shirdi is a pilgrimage town, and almost everything of note is connected to the life and memory of Sai Baba. The main temple complex is large enough to take half a day; the surrounding pilgrimage circuit, the Sakori Ashram, and the town's quieter back streets can fill another half. Secular sightseeing is limited — this is not that kind of town.
The atmosphere is particularly intense around the Aarti prayer ceremonies, held five times daily in the main temple. The most important are at dawn (Kakad Aarti) and noon (Madhyana Aarti), but all are worth attending if the crowds are manageable.