Yes, 3 days are enough for Valencia. It is a city full of attractions, from its vibrant cultural life to its incredible beaches. Within three days, you can get a good taste of what Valencia has to offer. You can explore the city's historical centre, visit the City of Arts and Sciences and take a relaxing stroll along the beach. Within three days, you can also enjoy some of the city's famous gastronomy and nightlife. However, for a more in-depth experience of the city’s offerings, it is always better to spend more time here.