Anacapa -- Families with children might want to start here, and they will want to be especially cautious near the island's unfenced cliff edges. There are more organized activities here than on the other islands, and the crossing to Anacapa is the shortest. If you're interested in sea kayaking, Anacapa's scores of sea caves make it your best bet. Though much smaller than its huge neighbor Santa Cruz, Anacapa has several times more caves, many of which are accessible by kayak.
Santa Cruz -- It has fewer caves than Anacapa, but Santa Cruz, the largest of the islands, is still a good choice for sea kayakers -- on Nature Conservancy land, the island's Valdez Cave (or Painted Cave) is the largest and deepest sea cave in the world. The Nature Conservancy owns much of Santa Cruz, and you must apply for permission to visit the portions of the island it manages. Backcountry enthusiasts, take note: Landing at Prisoner's Harbor here allows for the most challenging hikes in the park. It's also a good pick for families with younger kids.
Santa Rosa -- This is a good bet if you want to visit one of the islands for more than a day. (It's relatively big, so there's more to explore.) Those interested in ranching history and vaqueros (Mexican cowboys) will find Santa Rosa appealing. Santa Rosa's hundreds of undisturbed archaeological sites (please leave them undisturbed) also may attract anthropology buffs and others interested in Chumash culture. (The Chumash were the American Indians who inhabited all five of the islands.) Those interested in endemic plant life will probably also enjoy a visit. Though a century of ranching has wreaked havoc on the island's traditional landscape, the prehistoric stand of Torrey pines is spectacular -- the species grows in only one other spot on Earth (near San Diego).
San Miguel -- If adventure is what you're after, the choice is pretty simple: The ranger-led 16-mile trek to Point Bennett and back offers the greatest diversity of scenery among the park's hikes. San Miguel is also your best choice if you want to observe wildlife -- over 30,000 seals and sea lions gather at Point Bennett, and seabirds nest on Prince Island at the mouth of Cuyler Harbor.
Santa Barbara -- This is the smallest of the island chain, not to mention one of the most distant and solitary. After a 3-hour boat trip, you'll be free to hike this tiny island as alone as you care to be.
If you have only a day, Anacapa and east Santa Cruz are the closest to the mainland and the easiest to get to. The bad side: They're the most crowded (though crowded is a relative term here).
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.