What was the planned second stage of Operation Downfall, aimed at the Tokyo region?

Operation Coronet was the planned second stage of Operation Downfall, aimed at the Kanto Plain near Tokyo. It was tentatively scheduled to begin on March 1, 1946, after Operation Olympic’s proposed invasion of Kyushu.

Coronet would have involved landings on the Kanto Plain, the broad region surrounding Tokyo. Planned landing areas included Kujukuri Beach on the Boso Peninsula and beaches near Hiratsuka on Sagami Bay. Allied forces would then have advanced toward Tokyo.

The operation was designed to use airfields and staging areas captured during Olympic. It was never launched because Japan surrendered in August 1945, making the planned invasion unnecessary.

Coronet is easy to confuse with Olympic because both belonged to Downfall. Olympic targeted southern Kyushu first; Coronet was the later operation directed against Honshu and the Tokyo region.