La Tomatina is the reason Buñol is known outside Spain. On the last Wednesday of August, truckloads of tomatoes are dumped into the centre and thousands of people spend an hour throwing them at each other.
It is fun, messy, and tightly controlled. The festival is ticketed, crowds are heavy, and the town is not the place for a casual wander that day. If you want Buñol at its most local and relaxed, come at another time.