I love Fair Wind, for several reasons, starting with its home in Keauhou Bay, 8 miles south of Kailua Pier and so that much closer to Kealakekua Bay, where its two very different but impressively equipped boats head for snorkel/dive tours:

Fair Wind II: When traveling with kids, I book a cruise on the Fair Wind II, a 60-foot catamaran that includes two 15-foot water slides, a high-dive jump, playpens, and child-friendly flotation devices with viewfinders, so even toddlers can take a peek at Kealakekua’s glorious sea life. Year-round, the Fair Wind II offers a 4 1/2-hour morning snorkel cruise that includes breakfast and a barbecue lunch; most of the year it also sails a 3 1/2-hour afternoon snorkel cruise that provides snacks, which in summer becomes a deluxe 4 1/2-hour excursion with barbecue dinner. Swimmers age 8 and up can also try SNUBA—kind of a beginner’s version of scuba—for an optional $69, with an in-water guide.

Hula Kai: When traveling with teens or adults, I prefer the Hula Kai, the Fair Wind’s 55-foot foil-assist catamaran, open only to ages 7 and up. The boat provides a plusher experience (such as comfy seating with headrests) and, on its 5-hour morning snorkel cruise, a faster, smoother ride to two uncrowded Kona Coast snorkeling sites, which vary according to conditions (but not usually Kealakekua Bay). Guests have the option to try stand-up paddleboarding, SNUBA, or the propulsive “Sea Rocket” ($25 per half-hour) to cover even more ground underwater. The Hula Kai also offers a fascinating night snorkel/dive with manta rays, a 1 1/2-hour tour that doesn’t have to voyage far from Keauhou Bay to find them. Although you can see these gentle giants (no stingers!) during the day, at night they’re lured closer to the ocean’s surface by the plankton that also rise there. Like other tour companies, Fair Wind uses dive lights to attract even more plankton; on the off chance you don’t get to see a manta ray, you’re welcome back another evening or on afternoon snorkel tour. It’s fairly balmy at night, but you’ll be tempted to stay in the water with the magnificent rays as long as you can, so wetsuits, warm soup, and hot drinks are provided to ward off chills. One-tank scuba dives are also available on all Hula Kai excursions ($31 without gear; $45 with); the manta night trip also charges $45 per “ride-along” (no snorkeling) passenger.

Note: Many of Fair Wind cruises sell out several days in advance, or as much as 2 to 3 weeks in peak season, so book ahead.