San Juan is a monster celebration that marks the summer solstice. It’s celebrated across Spain, and Ciutadella is one of the best places to see the festivities. The street parties go on for three or four days, but the headliner is the famous horse-riding procession. Watch as black stallions rear up into the air, and locals surge forward to touch the horses’ chests. Then get ready to be pelted with hazelnuts. It might sound bizarre, but it’s not an act of aggression – each nut actually represents a kiss.