Phang Nga Bay, the limestone islands off Phuket and Krabi

Sail into Phang Nga Bay on a calm morning and the scale of it takes a moment to understand. The water is shallow, still and jade-green, and out of it, in every direction, rise islands that look as if they belong in a Chinese scroll painting: towers and pinnacles of grey and rust-streaked limestone, their sides sheer, their tops crowned with jungle, some no bigger than a house, some the size of hills. Between them, mangroves line the shore and the channels wind away into the haze.

The bay lies on the Andaman coast of southern Thailand, between the island of Phuket to the west and Krabi to the east.

How the islands were made

The towers are karst, limestone shaped by water. The rock was laid down long ago as a reef in a warm sea; over ages it was raised, then dissolved and carved by rain and the sea, leaving the hardest parts standing as towers, and the softer parts as caves, arches and hollows. The sea has risen and fallen around them many times. The result is a drowned landscape of hills, with the valleys filled by the sea.

Inside some of the islands are hongs, Thai for rooms: lagoons open to the sky, enclosed by cliffs and reached through caves or narrow passages at the right state of the tide. Several islands in the bay and along the coast take their name from them, among them the Hong islands, and paddling a kayak through a low cave mouth into one of these hidden lagoons, with the walls rising sheer on every side and the sky a circle overhead, is the thing most people come for.

James Bond Island and Koh Panyee

Much of the bay is protected as the Ao Phang Nga National Park, created in 1981. Its best-known sight is Khao Phing Kan, with the needle of rock called Ko Tapu standing in the water just off it, which appeared in the 1974 Bond film The Man with the Golden Gun and has been called James Bond Island ever since. It is very busy with boats from Phuket and Krabi in the middle of the day.

Nearby, Koh Panyee is a fishing village built on stilts over the water at the foot of a steep limestone cliff, its houses joined by boardwalks. Most visitors stop for lunch; the village is a working community, and a little respect goes a long way.

Elsewhere in the bay, quieter islands such as Koh Yao Noi, between Phuket and Krabi, have villages, rubber plantations, rice fields and beaches facing a horizon of limestone stacks, and are a fine base for exploring the bay away from the crowds.

When and how to go

The bay is at its best in the Andaman coast's dry season, from roughly November or December to April, when the sea is calm and the skies are clear. In the south-west monsoon, from about May to October, the water can be rough and murky, and some trips do not run.

Long-tail boats, speedboats and larger tour boats all run trips into the bay from Phuket and Krabi. The best advice is to go early, before the crowds reach the famous places, or late in the afternoon, when the day boats have gone and the light on the limestone is warm. A kayak, paddled by you or by a local guide, is the way to get into the caves and lagoons.

Trips that go there

G Adventures' seven-night Journeys: Explore Southern Thailand departs in December and January. Its places are Ko Samui, Hong Island, Khao Sok, Krabi and Ban Ta Khun.

Explore's thirteen-night Thai Island Hopping, from Bangkok, travels to Trang and island-hops by way of Koh Hai, Koh Muk and Koh Lanta to Koh Yao Noi, with Ao Thalane and Krabi at the end. It departs in November, December, January and February.

Explore's eleven-night Discover Thailand combines the history of Kanchanaburi and the Hellfire Pass with the south, by way of Phetchaburi and Pranburi to Surat Thani, Khao Sok National Park, Koh Lanta and Krabi.

However you see it, try to have one moment in the bay without an engine running: in a kayak in a lagoon, or on a beach at Koh Yao Noi at dusk. The limestone towers are best seen in silence.