Penghu sits between Taiwan and mainland China like a stepping stone dropped in the Taiwan Strait, which made it militarily significant long before aviation existed. During Japanese colonial rule, the islands were served initially by Anshan Airfield on Chetian Island — a modest gravel strip 600 meters long and 200 meters wide, built for a navy light aviation squadron. By the late 1930s, wartime demands outpaced what Anshan could offer. Penghu was the closest Japanese-held territory to the Chinese mainland, and the military wanted something more capable.

A site on the island's southwestern tip was chosen, land was requisitioned, and workers leveled the ground through 1936 and into 1937. Construction finished on 21 September 1937. The new airfield — called Zhumushui — ran north to south across a 3,600-foot by 1,500-foot sandy landing ground. It was a utilitarian facility, built to a wartime schedule, planted on an island that geography had made indispensable.

By April 1943, the 30th Air Base Unit was operating from Zhumushui with Nakajima B5N torpedo bombers and Mitsubishi G3M attack planes. The base changed hands within the Japanese command structure as the war intensified — by May 1944 it fell under the Kaohsiung Garrison's jurisdiction, reflecting how quickly the Pacific front was shifting.

The Americans knew about the airfield. During the Taiwan Air Battle of October 12–14, 1944 — a massive carrier-based and land-based air campaign — the 383rd Task Force of the U.S. Army struck Zhumushui in force, bombing it heavily across three days. Between January and February 1945, the 901st Naval Air Force Magong Dispatch Team was stationed there. Then on 8 April 1945, four squadrons of the 345th Bombardment Wing's Fifth Air Force — the 498th, 499th, 500th, and 501st — sent 25 B-25J medium bombers not against the airfield itself but outward from it, attacking the Japanese fleet off the coast of Shantou. The old sand strip at Penghu had become a staging platform for strikes reaching deep into the final months of the Pacific War.

When Japan surrendered in 1945, the Republic of China Air Force took control of Zhumushui. The airfield served through the late 1940s and into the 1950s, but the jet age made it obsolete. Fighter aircraft and heavy transports needed longer, harder runways than a wartime sand strip could provide.

A new Penghu Airport was completed in Huxi Township in 1957. The air force relocated in 1964 under government order, and an army garrison moved in to fill the space. The field was renamed Wude. The Ministry of National Defense's Penghu Defense Command has controlled it ever since, under the name Wude Camp. Civilian access is restricted, photographs are discouraged, and no interpretive marker explains what happened here during the war years. The history exists in archive documents and a handful of research articles. On the ground, there is only a fence.

The peculiar thing about military sites is how thoroughly their closure can rewrite public memory. Zhumushui Airfield absorbed B-25 raids, hosted torpedo bomber crews, and dispatched strike missions across the strait — and yet it is, as its Wikipedia entry puts it bluntly, "little known." Not because historians haven't documented it, but because its gates have been shut for six decades.

The physical footprint endures: the old sandy ground is still there, maintained as an active military installation. But the wartime identity has been compressed into a footnote that most Penghu residents have never encountered. Sometimes the most honest thing you can say about a place is that its story is locked inside it, waiting for the fence to come down.