Black Hills State University gives Spearfish much of its year-round life. The campus sits on the west side of town, with low buildings, open lawns, and views toward the hills rather than the sealed-off feel of a large urban university.
It is not a major sightseeing stop, but it explains why Spearfish has more cafes, events, and ordinary local rhythm than its size might suggest. Check the arts and athletics calendars if you are staying overnight.