Port Royal Sound Foundation Maritime Center

The Port Royal Sound Foundation Maritime Center is the best small nature center in the region, and it costs nothing to visit. It occupies a former oyster canning factory at the water's edge in Okatie, on the highway between Bluffton and Beaufort, which the Beaufort tourism office aptly calls a hidden gem. The foundation's mission is to protect Port Royal Sound, one of the deepest natural harbors on the Atlantic coast and the heart of a vast estuary of rivers, creeks and salt marsh, and the center explains why that estuary matters. Inside, the centerpiece is a 3,000-gallon aquarium holding fish found in the sound, from the species anglers chase to the small fry that use the marsh as a nursery. Low observation tanks, set at a child's eye level, hold turtles, snails, crabs and other sea life, and touch tables invite children to handle shells and animal specimens. A 14-foot bateau, the traditional flat-bottomed skiff of Lowcountry watermen, is there for kids to climb aboard, and exhibits tell the human story of the sound, from Native Americans and European explorers to the oyster and shrimp industries that once filled buildings like this one. Outside, a long dock reaches over the water and marsh, where you can see the artificial oyster reefs the staff have built to restore habitat. The center runs story times, a speaker series, art shows and seasonal kayak trips. It is open Tuesday to Saturday, 10am to 5pm, with free admission and donations encouraged; some programs and workshops carry fees. Allow about an hour, longer with a program.

Why stop here: most visitors to Hilton Head never see the estuary that makes the whole region work, the vast system of marsh and tidal rivers between the islands and the mainland. The Maritime Center explains it in an hour, in a building that is itself part of the story. Children love the tanks and the bateau, and adults come away understanding why the oysters in Bluffton and the shrimp on every menu depend on the health of these waters. It is an ideal rainy-day stop and a perfect break on the drive to Beaufort.

Making the most of it: check the foundation's calendar before you go for story times, talks and kayak outings, which are among the best ways to see the sound with a naturalist. Walk out on the dock at any tide; at low tide the oyster reefs and mudflats are exposed and busy with birds and fiddler crabs, while at high tide the marsh turns into a sheet of water. Bring binoculars for herons, egrets and ospreys. The center's staff are knowledgeable and happy to talk, so ask about the reef restoration and the creatures in the tanks.

Plan it as part of a Beaufort day trip: from Hilton Head, the Maritime Center is on the way north, so stop for an hour in the morning, then continue to Beaufort for the national park visitor center, the Verdier House and lunch on Bay Street, and on to St. Helena Island and Hunting Island in the afternoon. Remember it is closed on Sundays and Mondays.