[OldMissileer]

In the case of Hiroshima they were aimed at a steel mill.

The designated aim point for Little Boy was a bridge where a river split in two. That was basically the center of the city and very easy to spot from the aircraft. The weather was near perfect and the bomb was drop on that aim point. The exact hypocenter was located a little southeast of the bridge.

[Half Vast Conspiracy]

The Aioi Bridge is what I am reading.

Thanks