A scenic one-hour drive brings you to the Katsuren Castle Ruins, the remains of the oldest castle in Okinawa, built in the 12th century. Walk up a long series of stairs to this hilltop venue with dazzling vistas and be rewarded with the stone walls and foundations of this designated UNESCO World Heritage Site. Stop to photograph Kaichu Doro, "the road in the middle of the sea," which extends 2.9 miles (4.75 kilometers) from the Katsuren Peninsula to Henza Island. Then it's on to the Okinawan Sea Salt Factory to learn how this mineral-rich natural seasoning with therapeutic properties is created. Watch the factory process through the large viewing windows and purchase a variety of products. After lunch, your last visit is the Southeast Botanical Gardens, where you'll stroll the 100-acre grounds, home to spectacular blooms, sparkling water features and an extensive collection of exotic trees.