The local market at the foot of the church in San Antonio's main square runs on weekend mornings and is one of the few places in town that reflects the island's slower, older self. Local producers sell vegetables, cheeses, preserves, and handicrafts; the pace is unhurried and the prices are reasonable by Ibiza standards.
It is a good place to pick up genuine Ibizan products rather than tourist tat — look for fig cakes (figues seques), artisan gin (Ibiza has its own small distilling tradition), and locally made pottery. The market is not large, but the square itself is pleasant, shaded by trees, and far enough from the resort strip to feel like a different town.