What was the planned second stage of Operation Downfall, aimed at Japan's Kanto Plain near Tokyo?

Operation Coronet was the planned second stage of Operation Downfall, aimed at Japan's Kanto Plain near Tokyo.

Coronet was scheduled to follow Operation Olympic, the proposed invasion of Kyushu. Its objective was the Kanto Plain on Honshu, the main Japanese island and the region containing Tokyo. The tentative start date was March 1, 1946, after Allied forces had established bases and positions in southern Japan.

The plan called for a very large concentration of American forces, with landings on beaches around the Kanto region. The operation would have been supported by troops and equipment released from the European theater and by forces involved in Olympic. Its projected scale made it one of the most ambitious amphibious operations ever planned.

Coronet was canceled when Japan surrendered before either stage of Downfall began. It is easy to confuse Coronet with Olympic because both belonged to the same invasion plan. Olympic concerned Kyushu; Coronet concerned the approach to Tokyo through the Kanto Plain.