They almost seem to float on the shimmering  surface  of  Palau’s  Southern  Lagoon, rounded knobs of ancient coral formations mantled  in  dense  emerald-green  foliage. Though most of them are uninhabited, this spatter  of  tiny  islands  805km  (500  miles) west  of  the  Philippines has  become famous  among  divers  for  its  rich  diversity of marine life. The warm blue waters are so clear  (up  to  30m/98-ft.  visibility)  that  even snorkelers get quite a show, but scuba divers   report   truly   awesome   experiences here,  with  breathtakingly  deep  drop-offs and  immense  submarine  caverns.  Walldiving sites such as the Blue Corner, the Blue  Holes,  the  German  Channel,  the Peleliu Wall, and the Ngmelis Drop-Off have  achieved  almost  legendary  status among divers in the know.

It’s the big fish that give the Rock Islands their  special  claim  to  fame.  Commercial fishing  has  been  banned  in  Palau for more  than  a  decade,  and  as  a  result, threatened  shark,  barracuda,  and  wrasse species, as well as turtles and dolphins and giant  clams,  thrive  around  the  island’s spectacular  reefs.  Tallies  vary  widely,  but there  are  somewhere  around  300  islands in  the  group,  spread  over  some  161km (100 miles) of ocean south of Palau’s largest  island,  Babeldaob.  Three  ocean  currents  converge  here,  which  means  that hundreds of migratory fish species pass in and  out  of  these  waters.  Several  World War   II   shipwrecks   provide   underwater landmarks  to  explore;  you  can  also  swim through  tunnels  in  certain  islands’  coasts to  reach  inland  marine  lakes,  populated with  rare  stingless  jellyfish,  a  snorkeling experience you’ll never forget.

For a great overview of the Rock Islands, take a speedboat tour from the main tourist town of Koror, about 20 minutes from the  airport.  These  tours  will  whiz  you around   to   secluded   coves,   jewel-like lagoons,  and  the  most  dazzling  strips  of white-sand   beach.   When   it’s   time   to get down to some serious diving, leading dive-boat operators include Fish and Fins, Neco’s Marine, and   Sam’s   Tours. For a little variety, you can also try kayaking  and  sport  fishing  around  the  islands; there  are  plenty  of  watersports  shops  in Koror, as well as at the leading resorts.

Exotic as Palau may seem, English is spoken everywhere, and the U.S. dollar is the main currency. You can easily base yourself in Koror, or book a berth on a liveaboard boat such as the Eclipse (book through Sam’s Tours) or the Ocean Adventure I and III (book through Fish and Fins).