Koh Tan, also written Koh Taen, is the larger island beside Pig Island and the one you see from Thong Krut pier. It has a small village, a strip of mangrove, a few homestays and no cars. For a boat tour its point is the reef on the side facing Samui, shallow enough to snorkel from a boat at anchor and calm on most mornings.
The boat anchors over the reef. Masks and snorkels come out, the catamaran adds paddle boards and a slide, and you spend forty five minutes to an hour in the water. Nobody lands; the beach on this side is coral rubble rather than sand.
Depends on the tide and the captain. Morning boats often do the pigs first while the beach is empty, then the reef. Afternoon boats reverse it so the snorkelling gets the better light.
Every boat tour on this site except the jet ski safari, which is a ride to the pigs and back.
A short guide to the reef and how to snorkel it.
There are a handful of homestays and a small resort, reached by longtail from Thong Krut. Tours do not include an overnight.
Shallow reef fish, some coral, occasionally a turtle. It is an easy beginner reef rather than a dive site, and visibility is best from February to August.