Similan Islands...

Considered one of the top ten world dive sites by diving professionals,
the Similans - a group of nine islands close to the Burmese border,
offer extensive reefs, fascinating underwater topography and great
visibility. The giant underwater boulders which lie stacked on
top of each other to depths of 90 feet and beyond, provide a home
for colourful anemones, soft corals, moray eels, and red grouper
as well as some of the bigger fish.
Each island has its own special dive sites with something for
both the novice and the experienced diver. Sites range from an
offshore reef which lies within 8m (26ft) of the surface and drops
off to over 35m (114ft) to , passages, overhangs and chimneys,
providing fascinating diving. The variety of marine life, from
tiny fish to large rays, offers some great photo-opportunities.
There are a number of dive companies which provide regular trips
to the Similans, during the high season between November and April,
and include all equipment. Private boat charters can also be organised,
costs depending on the quality and speed of the vessel and the
number of persons travelling. It takes about 3 hours, to get there,
depending on the type of boat.
For those who would like to spend a little longer in the Similans,
liveaboard (live on board) trips lasting between 4 - 7 days
are available during the high season.
Surin Islands...

Close to the Similans are
the Surin Islands which also offer excellent diving and snorkelling.
Koh Surin Neua (north island) and Koh Surin Tai (south island)
are the main islands in this group of five. The best diving is
in the channel between these two islands.
Like the Similan Islands, Surin Islands are best visited during
the months of December to March when the seas are at their most
calm, and for divers and snorkellers, water visibility is good.