Dennis Bakhuis

Dive site · sea · The Similan Islands

🇹🇭 Sharkfin Reef

Similan Islands, Phang Nga, Thailand

A long granite ridge running south from Island 3, with fins of rock breaking the surface — big enough that it takes two dives to see properly.

Dives here
1
Deepest
21.7 m
Water
salt
First · last
2013
Also known as
Sharkfin Reef Similan

Revision 1 · changed 10 Oct 2026

History
  1. r1 10 Oct 2026 Imported from the personal log · Dennis Bakhuis

Site data © divelog-sites contributors (ODbL), descriptions and maps CC BY-SA 4.0 · 53edcaf

1 map

Granite ridge↓20 m↓30 m↓40 m↓30 mUsual dive: south side, over the ridge, finish north · 219 mRock breaking the surface↓0 mRock breaking the surface↓0 mMain block, breaks the surface↓0 mMooringSwim-through↓14 mRidge top↓12 mRidge top↓8 mRidge top↓5 mSteep south side↓16 mBoulder↓15 mBoulder↓18 mBoulder↓15 mCoral field, north side↓18 mN20 m
  • Buoy
  • Point of interest
  • Marker
  • Pinnacle / rock
  • Depth contour
  • Dive path
  • Other area
  • Depth
Site map · 9 objects · 1 path · max 40 m

Shark Fin Reef, a ridge of granite blocks in the southern Similans whose tops break the surface like fins: the swim-through, the mooring and the depths, with the main block 40-60 m across (IDC Phuket) and the ridge about 400 m long; the north side is a gentler coral slope at 15-20 m, the south side drops steeply to 30-40 m, and the usual dive crosses the ridge from the south side to the shallower north for pick-up. There is no OpenStreetMap feature for the reef: the origin is the divezone position, 2 km east-south-east of Island 3 (IDC puts the start one mile south-east of it), so the position is uncertain. The site coordinates (8.545, 97.645) were 4 km north-west, near Island 4.

Map © divelog-sites contributors, CC BY-SA 4.0 · 53edcaf

A long submerged granite ridge running south from Similan Island 3, in the southern part of the archipelago, with rock outcrops breaking the surface along it that look like fins — which is where the name comes from, not from sharks.

It is unusually big for a Similan site, long enough to be dived twice in different halves, with two distinct sides: a canyon and swim-throughs on one, a sloping reef on the other.

Dived 26 November 2013 to 21.7 m.

Dived here with

Kim

Nearby sites

1 dive at Sharkfin Reef

  1. 26 Nov 2013 with Kim boat date26 Nov 2013 depth21.7 m time51 min water—

Sources

  • First-hand observation (Dennis Bakhuis)