Who hasn't heard of San Fermin? Thousands of people dressed in white with red scarves prepare to welcome locals and tourists to the Running of the Bulls. The party atmosphere is great fun, with a number of cultural activities scheduled, not just the traditional bullfighting. You'll need to get to the bullring early, at about 6 am, to be sure to get a good spot. It starts to fill up little by little, and before long it's completely packed. What an atmosphere! Book a hotel room early to avoid disappointment, and rest assured that you can explore the whole centre on foot.