Baccab jungle bike tour not up to expectations and overpriced. The Land Rover adventure my travel companion took was very exciting. Ship anchors 20 minutes from pier so you have to take a tender. Skuttlebutt is that Belize City is dangerous beyond the tourist pier. The ship excursions seemed expensive here. I was disappointed in the bike ride, companion traveler loved the Land Rover adventure for $100.
Hire a taxi at the pier for an island tour or to go to the beach. Private beaches cost about $10 to use beach chair and bathrooms. We went to Paradise beach. It was nice and you could rent snorkeling equipment or kayaks right there for less than you'll pay booking through ship. Coral reef quite close to shore for on-you-own snorkeling.
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