Wonderful Tri Trang beach Phuket, you can find this pretty beach in front of the Merlin resort, an excellent location for snorkeling; the beach is not the best for swimming due to the coral & make sure you check the tide schedule before you go.
I have been to this beach a few times, keep in mind during high tide,you must swim a nice 70 - 80 meters to reach the coral beds that you can see in the shallow & the deep water, if you have an underwater camera bring it along, the crystal clear water has plenty of pretty coral & colorful fish, is a site to see.
To get to this tropical gem take the road up the hill at the most southern finish of & follow it until you see the Merlin Beach resort, there is a dirt road alongside the resort which will lead you right to the beach.