Phú Quốc · Vietnam · Reef
An Thoi Archipelago
Up to 20 sites around 13 coral-ringed islands
Area photo: trungydang · CC BY 3.0
The An Thoi archipelago is the island cluster off the southern end of Phú Quốc, and it holds the bulk of the island's diving: up to 20 sites spread around 13 islands, with depths anywhere from 10 to 40 m. Most of the islands are ringed by coral and are slowly being converted to marine protected areas. Divers come south for more and bigger fish than the northern sites hold, and for nudibranchs.
Also known as An Thoi Islands.
Where it is and how deep
9.9543° N, 104.0176° EApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
Boats work a rotation of sites around the 13 islands — up to 20 of them in all. Profiles vary widely across the group: the shallow island margins start around 10 m, while the deeper edges run to 40 m, so the briefing matters more here than it does on the northern side of Phú Quốc, where none of the sites are deeper than 10 m. Coral rings most of the islands, and dives generally follow that fringe.
Current is the variable to plan around. It runs anywhere from mild to strong depending on the site and the day. What the south gives you over the north is size — more fish and bigger fish — along with a lot of nudibranchs on the coral itself, which is worth slowing right down for. Much of the archipelago is being brought under marine protection.
Marine life and season
- Nudibranchs
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Prime | Prime | Prime | Prime | Good | Fair | Off-season | Off-season | Off-season | Good | Good | Prime |
Season follows Phú Quốc: October to May is the dive season, best from November to April; June to September is the rainy season, when seas turn rough and several centres close.
Know before you go
- Currents here range from mild to strong depending on the site and the day; take the briefing seriously and stay with the guide when the flow is running.
- The crossing to the southern islands is more exposed than the northern route and the boat ride can be rough — worth planning for if you are prone to seasickness.
Dive videos
Scuba Diving Phu Quoc - An Thoi Archipelago · Phu Quoc on YouTube
Questions divers ask
How deep are the An Thoi dive sites?+
Depths across the group run from 10 to 40 m, so the profile depends on which of the roughly 20 sites the boat visits that day.
Are there currents in the An Thoi archipelago?+
Yes — mild to strong, varying by site and day. The southern part of Phú Quốc is less protected than the north, which also means the boat ride out can be rougher.
Sources
- Phu Quoc — Wikivoyage
- Hòn Thơm (OpenStreetMap) — OpenStreetMap
More dive sites in Phú Quốc
Reef
Two shallow coral sites: nudibranchs at 12 m, macro to 18 m
Reef
Rock canyons and hard coral from the surface to 12 m
Similar dives elsewhere
A rocky outcrop from 18 to 35 m with lionfish and batfish
Soft-coral ridge where mantas pass overhead
A wreck at 8 m and a drift south down a slope that reaches 40 m
A free descent in open water to a reef top at 24 m, sloping on to 35 m