The sun is just beginning to soften over Key West’s Old Town as certified divers gather near A&B Marina, anticipation rippling through the humid air. Across the street, the Hyatt Centric Hotel stands as a modern waypoint, hiding behind it the sleek dive boat, The Phoenix, ready to carry seasoned underwater explorers back into the vibrant world of the Florida Reef. This PADI Refresher Course offers more than a routine skill check—it’s a methodical reintroduction to the demands and delights of diving in one of the country’s most active marine ecosystems.