What was the launching point for the atomic bomb attacks against Japan?

Tinian Island was the launching point for the atomic bomb attacks against Hiroshima and Nagasaki, Japan. One of several islands in the Northern Marianas, Tinian is less than forty square miles in size and located approximately 1,500 miles south of Tokyo. The round trip flight from Tinian to Tokyo took B-29s an average of twelve hours. This proximity to Japan is one reason Tinian served as the headquarters of the United States Army Air Forces 509th Composite Group, which flew the atomic bombing raids.

Tinian Island was desired by the U.S. military because of its key strategic importance. It was easy to supply by sea and perfect for launching air attacks against Japan. Accordingly, the U.S. military referred to Tinian with the codename "Destination."

The taking of Tinian, which began in June 1944 and ended on August 1, was a very difficult feat. Over 300 Americans and 6,000 Japanese lost their lives. Nonetheless, Navy construction battalions known as the SeaBees began bulldozing mere days after the island was secured. Six runways were completed within two months and Tinian soon became the biggest air base in the world. North Field consisted of four airfields and supported 269 B-29s. Daily, the Twentieth Bomber Command launched relentless attacks on the Philippines, Okinawa, and mainland Japan.