A vast bay on the western side of Racha Noi gives home to Manta Bay, also known locally as 'Marina Bay'. A mixture of corals inhabit this dive site. Leather corals, sea whips, brain corals and patches of fire coral abound.  Manta Bay is usually blessed with good vis which can often reach up to 40+ metres. The bay itself has a mean depth of about 12 metres and has some pretty big bommies.

Just a few fin kicks westwards from southern the corner of the bay, are some huge submerged rock formations.  At around a depth of 18 metres are some pretty impressive swim throughs, decorated with some huge fans and soft corals. As you begin to enter sometimes it's hard to see the exit as they are invariably stocked with Five Line Snappers and Glassfish. There are a few of these awesome swim throughs to be enjoyed.

The main reef is usually dived in a southerly direction with the current. It slopes gently to more than 35 metres and it's possible to find much interesting marine life, such as Octopus, Turtles, Lionfish, Frogfish and more. Although the western side of Racha Noi doesn't match the east side in terms of marine life abundance, there's still plenty to keep you interested. Again, Manta sightings are common here, as they are at most dive sites around Racha Noi.