On Lou Island, volcanic glass once made this region matter to its neighbors. Obsidian from Manus spread through Melanesian trade networks for generations, used for tools and weapons, carried in canoes across hundreds of miles of open sea. The Tok Pisin name for obsidian - spia botel, meaning "bottle spear" - is a linguistic fossil of the trade, the word marking both what it replaced and what modern materials replaced it in turn. Mining largely died out in the twentieth century, but the name holds. The local diet still runs on sago, a starch extracted from the pith of palm stems that grow in places where nothing else will. It is almost pure carbohydrate. Visitors are welcomed into villages to watch the process, which involves splitting the trunk, pulping the pith, and washing out the starch in a rhythmic ritual that predates most other cooking techniques on the planet.

Papua New Guinea is a country of extraordinary dances - some ceremonial, some for tourists, some that have survived precisely because they were never shown to outsiders. Manus dances use the garamut, a slit drum carved from a single hollowed log, played with the palm or a heavy stick. The sound carries across water for miles; villages once used the garamut as a signaling system, each beat pattern a word. The same instrument appears in the Sepik region on the PNG mainland, but Manus dances have their own character - sensuous and economical, the movements small and precise, the accompaniment deep enough to feel in the chest. Watching one, the word "traditional" starts to seem inadequate. These are living performances, not preserved ones.

The provincial capital, Lorengau, sits on the edge of Seeadler Harbor with a population of about 6,000. In 1944 the Japanese held the town; by the end of that year the Americans had turned Seeadler into one of the largest naval anchorages in the Pacific, with airports, docks, and a fleet capable of invading the Philippines. Relics of that war are everywhere - landing craft rusting in shallow water, concrete foundations under the palms, the occasional Japanese bunker swallowed by vines. The town itself is reached by causeway from the airport on Los Negros Island, with a few roads radiating inland and a great deal of coastline. Beyond Lorengau, most transport is by boat. That is not a complaint. The boats are the best way to see what Manus actually is.

Rainforest covers most of the interior - thick enough that orchids flourish in the canopy, and the birdlife includes species found nowhere else. Possum and bandicoot move through the understory; wild pig have been hunted here for thousands of years. But the coral atolls are the draw for most travelers. Reefs surround the main islands and are reachable by outboard motor or canoe, the water so clear that at noon the shadows of fish on white sand seem to have their own geometry. Diving and fishing here are among the Pacific's least-visited and best-preserved. Dugong and sea turtles appear regularly enough that sightings are not remarkable. Sea kayaking has started to catch on. The province is easy to miss - Air Niugini flies in from Port Moresby, Lae, Rabaul, and Kavieng - but travelers who make the effort understand, almost at once, why Margaret Mead kept coming back.