Ko Phi Phi – Ko Bida Nok & Ko Bida Nai

Ko Bida Nok & Ko Bida Nai are the last two islands south in the Phi Phi Archipelago. These two small islands offer some of the best day trip diving in the Andaman Sea.

The Limestone Phi Phi islands are one of the most dramatically beautiful locations in the world. The scenery from the surface is absolutely stunning; colossal emerald green monoliths rising straight up out of the sea to heights of more than 500 meters. Underwater, these towers shape a rugged and varied environment for scuba divers and over time nature has sculpted canyons, overhangs, caves and swim-throughs in the soft limestone rock. There are vertical walls that plunge straight down to more than 25 metres. A wide spectrum of corals and marine species are to be found on the Phi Phi Islands. There are several Islands suitable for diving that are listed here:

Ko Bida Nok

The Jewel in the crown of the Phi Phi archipelago, the small island of Ko Bida Nok juts dramatically out from the ocean surface. The name literally translated from Thai means ‘Outer Father Island’ – because it is the last island south in the Phi Phi chain. Beneath the waves there is spectacular underwater topography, with vertical walls, crags, drop-offs, huge pinnacles, caves and swim throughs. This incredible underwater backdrop is decorated with an extensive range of corals – multi-coloured soft corals, sea whips, giant fans, harp corals, staghorn, gorgonians etc. The range and abundance of marine fish is no less impressive – shoals of two-spot snapper, blue streak fusiliers, five-line snapper, barracuda and much more. Packs of trevally hunt during the day on the millions of tiny damselfish that shelter on this site. If you are lucky you might see a banded sea snake or even some black tip sharks! Koh Bida Nok has it all.

Bida Nok has a small bay at the south side of the island, which is suitable for snorkeling or first-time divers. Ironically it’s often the snorkelers that see the sharks as they like to cruise in shallow water. The bay is a good place to spot Kuhl’s stingrays buried in sand, or maybe find some reef crabs hiding under small coral bombies during the day.

The steeper west side of the island is more popular to dive as there is generally more to see, and more scope for exploring. Head out west over finger ridge and there is a steep wall, covered in corals andfish of all kinds. Further north along the island there are several swim-throughs, and two caves. One cave is at 20 metres but is very narrow and suitable only for cave-certified divers. The other cave is at five metres, beautifully surface lit & full of copper sweepers.

Koh Bida Nai

Ko Bida Nai is only 60 metres away and sits in between her sister, Ko Bida Nok and the much larger island of Ko Phi Phi Ley. (‘Nai’ means ‘inside’ in the Thai language)

Although smaller than Ko Bida Nok, Bida Nai is no less stunning, with similar underwater terrain, pinnacles & swim-throughs. The north end of the island is a vertical wall, covered in soft corals and dropping straight down to depths of 25 metres/80 feet or more. whereas the south end is shallower. To the south-east sit some deeper pinnacles that are less frequently dived, but are a haven for marine life.

  • Distance from Phuket: 50 km (31 miles)
  • Boat Trip average time: 3 hours
  • Depth: 3-30 metres (10-100 feet)
  • Visibility: Fair to excellent
  • Current:  slight to brisk

Ideal for: Nitrox, Deep Diver, Under Water photography, Under Water Naturalist, AWARE Fish ID, Search & Recovery Diver