Taking place in May every year, San Isidro is the world’s biggest bullfighting event. It definitely isn’t a festival for the faint-hearted. But if you are interested in experiencing or watching this traditional Spanish sport first-hand, this is the best time to go. Along with bullfights that take place as Las Ventas, the major bullring in Madrid, there are other events during the days of San Isidro, and you will find many locals dressed in the traditional costumes. It’s an exciting time to be in the city, whether you are keen to watch the bullfights or not – but if you are, make sure to buy your tickets as soon as possible because they tend to sell out many, many months in advance.