Is St. Thomas family-friendly?

Plan your first full day around Magens Bay on the north shore. The bay curves into a horseshoe that keeps the water inside shallow and flat a long way out, near 80°F most of the year, and lifeguards are on duty. The pavilion has restrooms, outdoor showers, and a snack bar a few steps from the sand, and entry runs around $5 per adult at the gate. By noon the sand is hot enough that toddlers will want water shoes. When three ships are docked at Havensight, get there before 10 a.m., because the cruise taxis fill the parking lot by late morning. On the East End, Lindquist Beach in Smith Bay Park is quieter, charges a small fee, and has no vendors, and the only shade comes from sea grape trees. Brewers Bay, next to the University of the Virgin Islands, is free and calm, and jets roar low overhead as they land at Cyril E. King Airport, which some 5-year-olds rate above the fish.

Coral World Ocean Park at Coki Point is the one paid attraction worth the money for children under 10. Its underwater observatory puts kids at eye level with parrotfish and tarpon about 15 feet down, and in the touch pools small hands can feel the rubbery skin of a sea cucumber. Budget roughly $30 to $40 per adult, with a lower child rate, and allow 3 hours. Sea Trek, the helmet walk along the seabed, has a minimum age of around 8, and the main ticket page tends to bury that rule. Coki Beach, next door, has the island's best beginner snorkeling, with sergeant majors crowding the shallows within 10 feet of shore, but it comes with trade-offs: vendors push chair rentals and fish food hard, the sand gets crowded on cruise days, and black sea urchins cover the rocks at both ends, so pack reef shoes.

Strollers struggle across St. Thomas. On Main Street (Dronningens Gade) in Charlotte Amalie, sections of sidewalk narrow to a single person's width, and the 99 Steps up toward Blackbeard's Castle are a straight climb on brick and stone, so bring a carrier or skip them with children under 6. Fort Christian, the red-walled fort on the waterfront, is flat and compact enough for a 40-minute visit, with a museum inside. Safari taxis are open-air trucks with bench seats and no seat belts, and the road between Red Hook and town climbs steep switchbacks. If you rent a car, Americans should know that traffic drives on the left in American left-hand-drive cars, and you will want your own child seat. The ferry from Red Hook to Cruz Bay on St. John takes about 20 minutes, and it's that crossing that leads to the best day trip from the island, the underwater snorkel trail at Trunk Bay in Virgin Islands National Park.

For bed space, Secret Harbour Beach Resort on the East End rents studios and one- and two-bedroom suites with kitchens, on a calm beach where you can snorkel straight off the sand. Read each condo listing in Sapphire and Red Hook line by line, because many that say they sleep 6 count a sofa bed. The Ritz-Carlton, St. Thomas runs a Ritz Kids club, at Ritz prices. Groceries cost well above mainland rates, and a kitchen combined with a stock-up at Moe's Fresh Market in Red Hook saves a lot over four days of restaurant meals. Picky eaters usually manage pates, fried pastries filled with beef, chicken or saltfish, sold at roadside stands for a few dollars each, and you can smell the hot oil and thyme from the car. Johnnycakes, a slightly sweet fried dough, are easy wins with children under 5. Many rentals draw tap water from rooftop cisterns, so mix formula with bottled water.