Chuuk's identity as a travel destination is defined almost entirely by what lies beneath its lagoon. The wrecks of Operation Hailstone — the February 1944 US Navy air attack that sank the Japanese Combined Fleet anchorage in a single day — remain exactly where they went down, now draped in coral and teeming with marine life. Above the water, the islands offer hiking, birdwatching, and a close look at traditional Micronesian life.