HIJMS Nagato

The battleship Nagato was Admiral Yamamoto's flagship when the Pearl Harbor operation was set in motion, which gives her afterlife at Bikini a heavy symmetry: assigned as a target for the 1946 tests, she absorbed the Baker blast and sank quietly a few nights later. She lies upside down, hull toward the surface, and the classic tour runs to the four enormous propellers standing in file off the stern — one of technical diving's defining photographs. Under the flared bow, teams can sight the muzzles of sixteen-inch guns pressed toward the sand. Depth, orientation, and history demand, and receive, complete seriousness.

The moment you come for: The four propellers; 41-cm gun muzzles beneath the inverted bow; the flagship connection to December 1941.

Topography: Capsized hull resting on its superstructure at roughly 50 m

Entry: Expedition diving only, planned as a decompression dive from the first briefing.

Hazards: Working depths beyond 45 m with mandatory decompression; confined inverted spaces; absolute remoteness from medical care.

Conservation: Within the UNESCO-listed test site and treated with memorial respect; nothing is removed, and penetration follows expedition protocols only.