Richelieu Rock rewards both kinds of underwater curiosity: the diver watching a school of fish sweep past, and the one absorbed by a tiny animal beside a sea fan. This isolated pinnacle belongs to Surin National Park in Thailand’s northern Andaman Sea. A whale shark would be a wonderful bonus; the reef does not need one to make the trip memorable.
Dive dates appear when the writer supplied them. Earlier stories keep their original words and have no newly assigned ratings.
A horseshoe of reef with more than one story
Richelieu combines schooling fish with fascinating small life. Its limestone rises in a curved formation, with a shallower southern interior and deeper outer faces. Soft corals, anemones and sea fans give the rock much of its colour, while detached pinnacles add further relief nearby.
The reef and the blue
Silver schools and colourful reef faces share the same view.
A closer look at the larger scene
Barracuda, trevally and other schooling fish are documented here. A series of dives can show different aspects of the rock, but the route belongs to the day’s briefing: exposed water, current and diver traffic can change where the group spends its time.
The small-life side
There is plenty to notice even when no large visitor appears.
Why macro photographers enjoy Richelieu
Seahorses, ghost pipefish and harlequin shrimp are among the animals reported by local operators. Their camouflage is part of the appeal. A slow, well-controlled look can be more rewarding than trying to cover every corner of the site in one dive.
Conditions matter: current can become strong and visibility can fall substantially. The shallow top does not turn an exposed offshore pinnacle into a sheltered beginner site. An operator’s acceptance and an appropriate profile depend on certification, recent experience and conditions.
Meet the reef: six fish to know
Schooling fish, small reef residents and one possible giant visitor offer very different reasons to look closely. These illustrations are representative, not photographs of encounters.
Whale shark
An occasional visitor from the blue. Its appearance is a bonus, never a reason to promise a particular outcome for a booked dive.
Barracuda
Long silver shapes are part of Richelieu’s schooling-fish appeal. The actual size and position of a school change from dive to dive.
Giant trevally
A powerful, deep-bodied fish documented by Big Blue at this pinnacle. Watching the school is a very different pleasure from searching the reef for tiny animals.
Tigertail seahorse
Big Blue identifies tigertail seahorses among Richelieu’s macro highlights. Its small size and camouflage make a patient look especially rewarding.
Moray eels
Pirate Divers documents morays among the site’s reef life. This representative illustration stands for the group, without identifying every eel encountered here as one species.
Anemonefish
Anemonefish appear in the operator’s Richelieu gallery. Different anemonefish species have different markings; this illustration represents the wider group.
Wildlife sources and illustration notes
Big Blue’s site guide and photographs document the whale shark, barracuda, giant trevally, tigertail seahorse and anemonefish. Pirate Divers also documents morays. Checked 12 November 2026. Whale shark, clownfish, trevally and seahorse artwork was created with AI assistance for Divezone; moray and barracuda artwork comes from the existing illustration collection.
Where is Richelieu Rock?
The pinnacle lies east of the Surin Islands, in the northern Andaman Sea. The satellite map uses an approximate site reference near 9.3634° N, 98.0220° E, consistent with the geolocated Richelieu photographs. It identifies the area, not a mooring, an entry point or a navigation waypoint.
The shape of Richelieu Rock
This oblique illustration shows the broad horseshoe form and its contrast between shallow reef and deeper surroundings. It is an interpretive sketch, not a measured survey; small pinnacles, distances and relief are simplified.
Original Divezone illustration informed by the relief descriptions from Big Blue Diving Khao Lak and Pirate Divers and the historical 2006 Pocket Divesite plan displayed by Pirate Divers. It does not reproduce that plan or identify present-day moorings. Approximate seabed depth follows the operator descriptions.
Getting there and choosing a trip
Khao Lak is the practical mainland base for dedicated day trips. Liveaboards can combine Richelieu with Koh Bon, Koh Tachai and the Similan island group, but a cruise labelled “Similan” does not automatically include this northern stop. The operator’s actual programme is the useful reference.
Big Blue was advertising Richelieu day trips for 14 and 16 November 2026 when this page was checked. Those dated listings establish a current programme, not availability for another date. Pickup coverage, crossing time, equipment, park fees and cancellation terms belong in the chosen trip’s quotation.
Phuket can be a wider travel or liveaboard gateway; it should not be confused with a short local boat ride to Richelieu. A stay farther south usually means arranging a mainland transfer or joining a suitable multi-day cruise.
Video: Richelieu through a diver’s camera
Aaron and Cassie’s Richelieu Rock film accompanies their account of visits in November 2024 and April 2025. It shows a past experience, not a forecast of visibility, current or wildlife on your departure.
Video: Aaron and Cassie — Richelieu Rock Guide.
Richelieu Rock questions
Is Richelieu Rock in the Similan Islands?
It belongs to Surin National Park. Northern liveaboards often combine it with the Similan island group, which explains why the names appear together in cruise descriptions.
Can a newly qualified diver join?
The answer depends on the operator’s admission rules, your recent experience and conditions. Local guides describe this as intermediate-to-advanced offshore diving; an Open Water card alone is not a promise of access to every dive.
How deep is the site?
The top approaches the surface, while descriptions place the surrounding seabed around 35 metres. The depth of the site is different from an appropriate personal dive profile.
Will I see a whale shark?
Possibly, but an encounter cannot be guaranteed. Reef life and schooling fish are good reasons to enjoy Richelieu even when no whale shark appears.
Is a liveaboard required?
No. Dedicated day trips operate from the Khao Lak area during the park season. A liveaboard offers a different way to combine the site with other northern stops.
Is Richelieu suitable for a snorkelling companion?
This exposed pinnacle should not be treated as a sheltered snorkelling lagoon. A companion’s permitted activities, supervision and passenger fare need an operator-specific answer; other Surin island programmes may fit a snorkelling holiday better.
Why do the old reviews describe different conditions?
They record different visits. Visibility, current, boat traffic and wildlife can change substantially, so the visit date and circumstances are part of the value of a reader’s account.
Sources and editorial notes
Updated 12 November 2026. Khao Lak Scuba Adventures describes the relief, approximate seabed depth and variable visibility; its summary and narrative use different maximum-depth figures, so this guide separates the surrounding seabed from a personal dive plan. Aaron and Cassie provide the credited video context. The historical 2006 photographs retain their dates and licences. Original Divezone comments remain unchanged.
Access: Boat. See the map of Richelieu Rock on the right for the exact location.
Fishes you may spot while diving Richelieu Rock
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Barracuda
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Giant Trevally
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Leopard Shark
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Manta Ray
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Pipefish
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Whitetip Shark
... and more fishes & sea life, Dogtooth Tuna, Whale Shark
Photos
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Yellow Seahorse in Lembeh StraitPhoto by Agnes Tjandranegara -
Clown fishes waiting in front of their blue anemone housePhoto by Jihye Lee -
Blacktip Shark patrolling the crystal clear water... EPIC photo!Photo by Yann Hubert -
Huge Hammerhead Shark patrolling the reef in French PolynesiaPhoto by Yann Hubert -
Beautiful & Colorful Mandarin FishPhoto by Rich Guest -
Flying Ray Manta in Bali!Photo by Jihye Lee -
Lion Fish swimming in crystal clear waterPhoto by Agnes Tjandranegara -
Surreal LifePhoto by Jihye Lee -
Porcupine Fish Hiding In Pink Coral ReefPhoto by Jihye Lee -
LeopardPhoto by Jihye Lee
Diving Reviews for this region
Surin Islands
Island reefs and the offshore spectacle of Richelieu Rock, with day-trip and liveaboard options. Surin snorkelling and a pinnacle dive are different experiences with different requirements.
Liveaboard Reviews in Surin Islands
MV Smiling Seahorse
Photos: Smiling Seahorse operator gallery via LiveAboard.com.
The Junk
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MV Thai Sea
Thai Sea photographs supplied through LiveAboard.com. Images are undated and show the documented vessel, not a new inspection.
MV Miss Moon
Miss Moon photographs supplied through LiveAboard.com. Images are undated and show the documented vessel, not a new inspection.
MV Diverace Class E
This is a historical vessel profile, not a bookable liveaboard. DiveRACE confirms that Class E was lost following a fire in April 2025. The former boat’s photographs, description and reader memories are retained below as an archive.
MV Similan Explorer
The following account is retained as an archive. Prices, capacity, facilities, services and wildlife sightings mentioned here should not be used as current booking assurances.
SY Diva Andaman
Photographs supplied through LiveAboard.com. These undated images show the documented boat and activities, not a current inspection.
MV Marco Polo
Vessel photographs supplied through LiveAboard.com; capture dates are not supplied.
MV Deep Andaman Queen
Boat photographs supplied through LiveAboard.com; cabin details also illustrated by the operator. Images are undated.
MV Scuba Explorer
Scuba Explorer became Sawasdee FasaiThis is the former name of the boat relaunched as Sawasdee Fasai after a complete refit in December 2016. Scuba Explorer is not a separate current booking option.The Sawasdee Fasai profile covers the boat under its l
This is for sure the best dive site in Thailand and the best chance to spot a Whale Shark. It is better to go there on a liveaboard rather than on a day trip.
Hello! Just discovered your website and it’s amazing! congrats!
I dived richelieu rock last november on a liveaboard trip to the similans! just did my OWD back then and am surely spoiled now – first night dive at richelieu rock and it was unbelievable! sadly almost everything that came after in southern thailand and spain was fantastic but can’t fully compete with that! everyone who gets the chance to dive there – do it!!
Thanks Denise! Hope you enjoy what you’re seeing and about to read and discover on our site. We at Divezone are very interested on your liveaboard trip. How was it like? We would be more than happy if you’d share your liveaboard report here on Divezone. It will definitely help a lot of divers out there, who plans to do liveaboard around Richelieu Rock. Happy diving!
Yep, when I see ur photos I can’t wait to go diving again!
Everything was organized perfectly, the cabins were clean, with air con, water bottles, european plugs for cameras and stuff… it was a pretty big boat considering that we were only 10 divers. the food was awesome and varied (4 meals a day!), the crew was polite and a bit crazy – we had a lot of fun! before every dive we had a briefing of course, first all together, then again with your instructor or guide.
and to be honest: it’s heaven to be out of touch for a couple of days… no phone, no internet,… hmmm, no I wanna go back! 
okay, the liveaboard trip… it was organized by a dive center in chalong, phuket, where I did my OWD last year and I was lucky enough to have my private instructor who was willing to take me to the Similans AND to go on nov 6th, so just after the national park reopened again after the annual coral recovery period! so we went to kao lak and got on a boat called ‘peter pan’ for 4 days and we were 7 guests + instructors + crew. I know I repeat myself but I was VERY lucky! Usually there are way more people on a boat this size! but the season just began… we left kao lak soon after midnight and we woke up the next morning in another world
they planned 4 dives/day, morning, lunch time, afternoon and 3 night dives.
from kao lak we went straight up to, koh bon, koh tschai, then richelieu rock where we did 2 dives and then I had my first ever night dive(!!) at richelieu rock – it was stunningly beautiful! the next day we dived elephant head rock (awesome!! 2nd fav dive site!!) anitas reef, tuna wreck, east of eden, shark fin reef…
seriously, this was one of the best experiences I’ve ever made! I know, I’m just diving for a year now and there’s a lot out there, but such a liveaboard trip… I could get used to a life like this
peter pan andaman diving did a great job! well organized pick up, time management, they have great guides, everyone (tour leader, photographer, even the driver, cook, crew,….) was really really nice, they’ve got a very talented video- and photographer on board who makes you a video if you like to for a reasonable price.
what else can I say!? A perfect trip! I’d recommend everyone who wants to see richelieu rock or the simians to go on a liveaboard, cos this is the perfect way to get the most benefits out of a dive trip and to really enjoy your time without hurrying back every evening, it’s just a long way back and forth if you do day trips.
after 4 wonderful days we went back to Phuket Town harbor and the mini bus took us back to the hotels and apartments,
we had a guitar, dvds, book, the sun and our buddies
hope I was able to help a bit!
Best dive site in Thailand, for sure!
Went there on liveaboard Nov 2014. 7 other boats there on morning dive so far too many homo sapiens. Up to 14 boats may gather there. The late afternoon dive was exquisite with only one other boat. Millions of shoaling small and medium sized fish. Gorgeous reef covered in mauve soft coral and every reef creature possible. Flirting cuttle fish allowed us within 2 inches of them and one diver gently stroked them. Definitely in my top 2 dives ever.
Hello! It’s possible to do a day trip in richelieu rock on 26 or 27 or 28 of December? I will be those days near khaolak
Thanks!
Is this site too difficult to new graduate open water? I’m planning to dive at Richelieu on November.
Hi there!
Richelieu Rock is ranked as an “intermediate level” diving site because there can be strong currents. That being said, I hear that lot’s of time there isn’t much marine current. Best advice would be to dive with a very good boat, experienced and knowledgeable, they will evaluate your skills and make a proper decision.
Hopefully, someone comes around with a more precise answer from its own experience?
Thanks for reading Divezone! Safe bubbles!
I was really unlucky diving here – went in January and the visibility was 5m. Needless to say I saw hardly anything as the water was incredibly turbid.
Dive site was also quite congested – lots of liveaboards, lots of divers.
Careful planning is a must here – don’t take for granted that it will be amazing all year round and don’t take the liveaboard operators word for it.
I wish I had researched the liveaboard better and read the bad reviews too!
Highlights for me here was seeing how healthy the coral looks – some beautiful carpet corals and Gorgonians. I believe the hype!
Hi Faye!
I’m very sorry to read that the experience at Richelieu Rock wasn’t up to it’s reputation. I think it’s been a huge problem in Thailand both the degradation of the environment and the overcrowding of the diving sites.
Indeed, it’s always best to do research on dive center on websites like ours but also on diving forums. If you feel like i, you can research your liveaboard in the search bar – under the menu, top right hand side on Divezone – and leave a review of the boat, if we have a display page for it!
Thank you for reading Divezone! Looking much forward to reading more diving reviews from you!
My 13 years old son and I had 4 dives on Surin Islands in February 2019. We both qualified open water divers (=18m only) with not that many dives beforehand, but Richelieu Rock wasn’t a problem for us. We had a bit of a current on a second day in Richelieu, but we were able to adjust our dive to suit our experience and we had a great time. Visibility both days was about 12- 15 meters We saw 2 octopus, endemic tomato anemone fish, massive Napoleon wrasse, 14 (!) lion fish in one spot, barracudas that found me so interesting, that they came so close to me to check me out I was totally extatic to be surrounded by them and of course there are many more fishes! In fact shawls and shoals of them. Corals are also quiet healthy still there.
Ps. We did use a small dive shop with own speed boat that only take 18 divers. Liveaboards are not my “cup of tea” and we were on site with only two other boats in mid February, so we were lucky!