The Sapodilla Cayes make up the hooked southern end of the Belize Barrier Reef and the continental shelf, and they offer incredible wall dives and very few dive boats. There are also a number of more gradual walls. In general, most sites offer either beautiful coral formations or lots of fish, but rarely both.
For fishing, the waterways and sea around Punta Gorda [1] offer anglers the rare chance to bag a grand slam (permit, tarpon, bonefish, and snook). Fly-fishing is generally possible between November and May, in shallow areas around the cayes, mangroves, and river mouths. Reel fishing is available throughout the year, up the rivers or in the ocean; cast for snapper, grouper, jacks, barracuda, mackerel, or king fish. Most guides help you bring your fish back and find someone to cook it up for you. Fishing trips can run upward of US$400–500 for four people.
Links:
[1] http://www.moon.com/destinations/belize/punta-gorda-and-the-toledo-villages/punta-gorda