Koh Haa Yai

"Koh" means "island," and "Haa" means "five." Confusingly, however, Koh Haa consists of six small islands located west of Koh Lanta. “Yai” means “big,” so it literally translates to “the biggest of the five islands.”

There are several different options for diving here. Divers usually anchor on the southeast side, where there is a beautiful plateau at a depth of 3–8 meters, followed by a steep wall that drops to about 25 meters. You follow this beautifully overgrown steep wall along the left side of the reef; at a depth of 20 meters, there are some lovely gorgonians and sea fans. They are home to ghost pipefish.

A real highlight is the “Cathedral,” a huge cave that you can enter at a depth of 15 meters, then dive through a large opening—which connects the two parts of the cave—to the second chamber at 9 meters and into the cave itself. Inside the cave, you can surface and admire the impressive stalactites hanging from the ceiling. The interior of the cave rises to approximately 25 m above sea level and is constantly supplied with fresh air through a small opening. The play of light and the stalactites on the ceiling create a mystical atmosphere, offering great opportunities for photos.

If you decide to surface inside the cave, the dive profile unfortunately becomes a bit of a “yo-yo” experience, because you then have to descend again to a depth of at least 5 m to swim to the cave exit and then surface out of the cave. The entire cave system is flooded with light thanks to the large cave entrances.

The reef plateau, located to your right and at a depth of 3–10 meters, offers the perfect spot for an extended safety stop and a search for octopuses hiding here.

The Koh Haa archipelago is also well-suited for night dives—except inside the cave, of course.