Racha Yai, Siam Bay - Similan Islands
Siam Bay on Racha Yai is a gentle introduction to diving in the region, particularly good for those just getting started or brushing up their skills. Dropping to a maximum of 14 metres, it's a sheltered spot with a sandy bottom and scattered coral bommies. You'll often find a decent assortment of reef fish here: parrotfish chomping away, small groups of snapper, and sometimes a blue-spotted stingray resting on the sand. It’s a comfortable, easy dive, perfect for getting reacquainted with your buoyancy without any tricky currents to worry about.
- Location
- Similan Islands, Thailand, Southeast Asia
- Coordinates
- 7.611500, 98.370700
- Type
- reef
- Maximum Depth
- 14m
- Difficulty
- Beginner
Marine Protected Area: กำหนดพื้นที่เกาะราชาใหญ่ เกาะราชาน้อย ตำบลราไวย์ อำเภอเมืองภูเก็ต จังหวัดภูเก็ต
Best Time to Dive in Similan Islands
The warmest water temperatures in Similan Islands occur in May, averaging 30.8°C. The coolest conditions are in January at 28.6°C.
Monthly Water Temperatures
- January: 28.6°C
- February: 29.0°C
- March: 29.6°C
- April: 30.6°C
- May: 30.8°C
- June: 29.9°C
- July: 29.6°C
- August: 29.3°C
- September: 29.0°C
- October: 29.0°C
- November: 29.2°C
- December: 28.7°C
Nearby Dive Sites in Similan Islands
- 8 mile rock
- Andaman Scuba
- Anemone Reef (reef)
- Anita s reef - 5-20m (reef)
- Anita's Reef - 10-25m (reef)
- Anti gravity Divers
- Ao Kon Ka Re
- Ao Nui - 17m
- Ao Sane - 5-18m (reef)
- Ayara Bay - 17m (reef)
- Banana Bay - 5-20m (reef)
- Barracuda Rock - 20m (pinnacle)
- Batfish Bend - 10-28m (drift)
- Bay 1 / Ao Ter (reef)
- Beacon Beach
Nearest Dive Centres to Racha Yai, Siam Bay
- ABC Phuket Diving
- Activity and diving centre
- Adang Sea Divers - SSI
- All 4 Dive - PADI
- All4Diving® Phuket - ["PADI"]
- Amazing Phuket adventures - SSI
Marine Life in Similan Islands
Home to 183 recorded species including 127 reef fish, 38 hard corals, 9 seagrass & algae, 4 sharks & rays, 2 other, 1 octopus & squid.
Notable Species
- Whale Shark (Rhincodon typus) - Sharks & Rays
- Staghorn coral (Acropora kosurini) - Hard Corals
- sorrah shark (Carcharhinus sorrah) - Sharks & Rays
- Staghorn coral (Acropora indonesia) - Hard Corals
- seagrass (Halophila ovalis) - Seagrass & Algae
- Dusky Parrotfish (Scarus niger) - Reef Fish
- Bicolor Blenny (Ecsenius bicolor) - Reef Fish
- Moluccan cardinalfish (Ostorhinchus moluccensis) - Reef Fish
- Staghorn coral (Acropora secale) - Hard Corals
- Staghorn coral (Acropora valida) - Hard Corals
- Staghorn coral (Acropora hoeksemai) - Hard Corals
- cymodocea (Cymodocea rotundata) - Seagrass & Algae
- Herringbone butterflyfish (Chaetodon triangulum) - Reef Fish
- Dollfus's octopus (Amphioctopus aegina) - Octopus & Squid
- Clown Tang (Naso lituratus) - Reef Fish
- Staghorn coral (Acropora solitaryensis) - Hard Corals
- Species code: Ea (Enhalus acoroides) - Seagrass & Algae
- Blue-scaled wrasse (Cirrhilabrus cyanopleura) - Reef Fish
- Argus Grouper (Cephalopholis argus) - Reef Fish
- Staghorn coral (Acropora austera) - Hard Corals
Recommended Packing List for Racha Yai, Siam Bay
Based on average water temperature of 29.4°C, currents 7 cm/s.
- Shorty or Rashguard - warm 29°C water needs minimal exposure protection
- Mask - essential for every dive
- Fins
- BCD - buoyancy compensator
- Regulator - your most safety-critical piece of gear
- Dive Computer - tracks depth, time, and NDL
- Surface Marker Buoy (SMB) - essential for boat pickups
- Dive Torch - useful for crevices and colour at depth
- Underwater Camera - capture your diving memories