Atsugi Emergency Airstrip

The original Imperial Japanese Navy airfield was closed following Japan's surrender at the end of World War II in 1945. The U.S. military then took control of the site and converted it into a dedicated communications and signals intelligence base, removing its primary function as an active airfield. The final closure in 2015 was due to the land being returned from the U.S. Forces Japan to the Japanese government as part of a military realignment plan.

The site is currently a large, vacant plot of land. After its return to Japan in 2015, all U.S. military structures, including the large antenna arrays, were demolished and the land was cleared. The city of Yokohama is now preparing the site to host the International Horticultural Expo 2027 (GREEN×EXPO 2027).

The site was originally an airfield for the Imperial Japanese Navy's Yokohama Naval Air Group during World War II. After the war, it was repurposed by the U.S. Navy and became the Kamiseya Communication Facility. It was a critical Cold War-era signals intelligence (SIGINT) and communications hub, notable for its two large AN/FRD-10 Circularly Disposed Antenna Arrays, nicknamed 'Elephant Cages'. The name 'Atsugi Emergency Airstrip' and the ICAO code 'JP-2128' appear to be informal or non-official identifiers, likely from third-party databases, as the site's primary post-war role was not aviation. It is a separate location from the active Naval Air Facility Atsugi (RJTA).

There are zero prospects for reopening the site as an airport or airstrip. The land has been permanently repurposed for major urban development. Following the 2027 Horticultural Expo, long-term plans for the site include the development of a new large-scale theme park, commercial facilities, and public parks.