Navy Underground HQ: Names in a Shell Casing

The Japanese navy built its headquarters here to defend Oroku airfield, one of its key bases on the island. The site’s own FAQ lists the hill’s advantages: it stood close to the airfield, it looked out over the whole area, and nothing would interfere with communications. At 74 metres above the sea, it was known during the war as Hill 74.

The hill, in other words, was still good for signals.

According to the site, about 3,000 officers and men dug the headquarters by hand in 1944, over about five months: some 450 metres of tunnels, about 20 metres underground. The FAQ also mentions another account, in which the digging began only after the great air raid of 10 October 1944, and the tunnels were still unfinished when the fighting came. It adds that local people took no part in the work, because the project was top secret.

About 300 metres of the tunnels, centred on the commander’s room, were restored and opened to the public in March 1970. The way in is down 105 steps.

The walls show how it was done. The tunnels were dug entirely with picks and hoes, the museum says, and in places the rock is covered with short, narrow gouges, row after row.

And there was a signal room. Some 2,900 messages were sent from that small space, according to the site.

It is the best-known message sent from these tunnels: from Minoru Ōta, commander of the navy’s Okinawa Base Force, to the Vice-Minister of the Navy, on 6 June 1945, at 20:16.

It begins with an explanation. Reporting on the people of Okinawa, it says, ought to be the governor’s job, but the prefecture no longer has any means of communication, and the army headquarters has none to spare. Ōta had not been asked by the governor. He was sending it anyway.

What follows is an account. Since the attack on Okinawa began, it admits, the army and navy have been so taken up with the fighting that they have had almost no time to spare for the people. All the young and middle-aged men have been mobilised for defence. The old, the children and the women have lost their homes and belongings to the shelling and bombing, and are living in small air-raid shelters, in places where they will not get in the army’s way, exposed to wind and rain. Young women have volunteered as nurses and cooks, to carry ammunition, even to join attack parties. When the army changed its plans and assigned residents to distant areas, they moved at night, in the rain, with no transport. Throughout the fighting they have been made to work for the army and to go without. Food will last until the end of June.

Then the last line, roughly: The people of Okinawa fought thus. I ask that, in the years to come, they be given special consideration.

The telegram is remembered for that line. Most of it is about what the war, and the army, had demanded of them.

It is still a commander’s report, written from where he stood. It is not the testimony of the people it describes.

One week later, on the night of 13 June, Ōta and six of his staff officers killed themselves in the headquarters.

The search did not end there. Japan’s health ministry carried out its own recovery of remains in the tunnels in early 2025.

Ōta’s telegram was sent in a single evening. More than eighty years later, it is what this place is known for.

The list in the shell casing was not sent anywhere. It was rolled up, packed away and stayed underground, and it reached the family of one of the men on it seventy-eight years later.

Of everything sent from this hill, the message that took longest to arrive was the one nobody sent.