The 6th Bomb Group

North Field was built, starting on the site of the old Japanese Ushi airfield. The old airport area is located in the northwest corner of North Field. The U.S. incorporated the Ushi field service apron and many of the original Japanese buildings into the completed North Field. The atom bomb pits and the bomb assembly building are located north of the old airfield. So this part of North Field incorporates both the oldest and newest parts of the base.

From the National Park Service
A picture of North Field under construction, looking towards the east. The fan-shaped outline of the old airport can be seen in the first half of the left runway (runway Able).

From the Andrew J. Harvanek Photo Collection
A picture of the old airfield area taken in 1945, looking towards the northeast, with Saipan Island in the distance. The Ushi Field Service Apron is located in the lower left of this picture. The atom bomb pits are located halfway up the left side.

This map is from a National Park Service Brochure, available online.