Start your day by exploring one of the best-preserved Spanish colonial cities in the world during a sightseeing tour of Old San Juan. Duck into the Museo de las Américas to learn more about Puerto Rican history, walk the cobbled streets past colonial buildings, and tour the defensive structures that make up the San Juan National Historic Site, a UNESCO World Heritage Site. Opt for a more conventional walking tour, or zip around the 500-year-old city on a guided Segway tour.

While you could easily spend an entire day within the San Juan city limits, it would be a shame to leave without taking some time to bask in the warm Caribbean waters. Take the afternoon to snorkel or Snuba in the waters just off the coast of San Juan. To explore the water from the surface, opt for some surfing, stand-up paddleboarding, or offshore fishing instead. Lessons and tours are often beginner-friendly, so you don’t need any special experience to try something new.

All that activity has probably worked up an appetite, so reward yourself (and your taste buds) with a walking food tour through Old San Juan this evening. Learn about the island’s food culture as you sample artisan beers, rum cocktails, and typical Puerto Rican foods—think plantain and sofrito (a savory sauce made with peppers)—from local restaurants and cafés. You’ll also get the chance to admire the city’s colonial architecture illuminated at night. For something a bit more low-key, top off your day with a romantic sunset sail instead.