Most of the development on Koh Phi Phi Don has been concentrated on the sand-flats around the isthmus. Koh Phi Phi Ley is uninhabited. The rugged limestone cliffs of the island are home to populations of edible nest swiftels, whose nests are collected from inside large caves by local sea gypsies. There has been a huge growth in the diving business here over the past few years and there are now at least a dozen dive operators in the growing township of Ao Tonsai. The area offers a good variety of different types of diving with abundant hard and soft corals and healthy fish populations.
Local operators use either longtails or larger, specially converted boats.
The larger boats here also offer day trips to the more far-flung sites of Hin Musang, Anemone Reef, Koh Dok Mai and the King Cruiser Wreck. Snorkeling around the island is excellent, with plenty of shallow coral gardens on the fringing reefs which are alive with colorful fish. Sadly considerable anchor damage was inflicted on some of the popular snorkeling areas in the past. The dive follows around the island's northwestern apex. There is also an underwater pinnacle off the northeast shore.