Every year in the event area just across from Yoyogi Park, Tokyo celebrates Cinco de Mayo which coincides with the long holiday of Golden Week in Japan. It's an awesome outdoor festival where you can enjoy eating delicious Latin food, listen and participate in some amazing Latin dancing and music, and last but not least you can shop for various Latin wares. The festival is on for two days so you can choose when to go or even visit both days. It's free to attend and you can also bring your children to enjoy the sights. I highly recommend this for some relaxation away from the hustle and bustle of Tokyo life.
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Find out more about Yoyogi Park.