Bay 1 / Ao Ter - Similan Islands
Bay 1, or Ao Ter, on Similan Island No. 1 is one of our favourite spots for a truly relaxed dive. Forget big pelagics and raging currents; this is a place to slow down, settle into the sand, and let the reef come to you. We often drop in and drift gently along the sloping reef, which rarely dips below 20 metres, making it ideal for longer bottom times. The hard corals, particularly the large table and staghorn formations, are a real draw here. We've spent entire dives just hovering over a single coral head, watching the tiny Redfin Triplefins dart about, or trying to spot the ridiculously camouflaged Freckled Anglerfish. They're masters of disguise, so a keen eye and some patience are rewarded. The Ostrich Gobies are abundant, often sharing their burrows with tiny shrimp, and we’ve consistently found groups of Yellowstriped Cardinalfish hovering under ledges. It’s a site that rewards macro enthusiasts and new divers alike – calm conditions and plenty to see without having to fight a current. Our best dives here have been in the morning, right after sunrise; the light catches the reef beautifully and the smaller critters are often more active before the day boats arrive.
- Location
- Similan Islands, Thailand, Southeast Asia
- Coordinates
- 7.607231, 98.377830
- Type
- reef
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)
- Beacon Beach
- Beacon Point
Nearest Dive Centres to Bay 1 / Ao Ter
- 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 Bay 1 / Ao Ter
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