Dennis Bakhuis

Dive site · sea · Phi Phi, Koh Haa and the southern Andaman pinnacles

🇹🇭 Koh Haa Yai

Koh Haa, Krabi, Thailand

The big island of the Koh Haa group, with the Cathedral caves on the south shore — air-filled limestone chambers hung with stalactites.

Dives here
1
Deepest
19.8 m
Water
salt
First · last
2013
Also known as
Koh Haa Yai

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

Plate and staghorn coralBouldersKoh Haa Yai↓20 m↓20 m↓25 mCathedral, cave 1↓15 mThe Cathedral, air pocket inside↓12 mWindow between the chambers↓9 mCave exit↓15 mCave exit↓14 mSwim-through↓12 mOverhang↓18 mField of whip coral↓20 mRock↓6 mBoulder↓14 mBoulder↓18 mBoulder↓12 mBoulder↓12 mBoulder↓16 mBoulder↓16 mBoulder↓22 mRock↓8 mN20 m
  • Point of interest
  • Marker
  • Pinnacle / rock
  • Shoreline
  • Depth contour
  • Coral / reef
  • Other area
  • Depth
Site map · 15 objects · max 25 m

Koh Haa Yai (Koh Haa No. 5), the largest of the Koh Haa islets; island outlines from OpenStreetMap. The Cathedral caverns on its southern shore, the swim-through, boulders and depths, on the OSM coastline (positions are approximate); the chambers open from low-tide level to 14 m, the first two are joined by a swim-through at about 9 m and the largest has an air space under stalactites (Phuket Dive Guide). The Chimney that the site description mentions is at Koh Haa No. 1 according to Phuket Dive Guide and is not drawn and the Lagoon between islands 2-4, 700 m to the north-east, is a separate dive and left off. The site coordinates (7.45, 98.98) are 10 km east of the islands; the origin here is on Koh Haa Yai.

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

Logged as Koh Tha Yai; the site is Koh Haa Yai, the largest of the five islets of Koh Haa (five islands), between Phi Phi and Koh Lanta.

What makes it is the Cathedral caves on the south shore — chambers with an air space above the water and limestone stalactites hanging from the roof, which is what happens when a karst cave gets flooded by rising sea level and keeps its ceiling. The Chimney, the vertical swim-through from about 4 m down to an exit at 17–18 m that often gets credited to Haa Yai, is at Koh Haa No. 1, not here.

The lagoon in the middle of the five islets is sheltered enough to moor in and is the group's other attraction.

Dived 27 November 2013 to 19.8 m.

Dived here with

Kim

1 dive at Koh Haa Yai

  1. 27 Nov 2013 with Kim boat date27 Nov 2013 depth19.8 m time52 min water—

Sources

  • First-hand observation (Dennis Bakhuis)