The Manhattan Project refers to the joint US-UK-Canadian determination to develop the atomic bomb. It was dubbed because the US Army component of this effort was initially headquartered out of 270 Broadway in NYC. The Los Alamos National Laboratory was built in a secluded spot nestled in the Jemez Mountains to house Project Y, the team tasked with actually developing and building the bomb, headed by J. Robert Oppenheimer. It was started because Albert Einstein warned Roosevelt that Nazi scientists were already working on developing an atomic weapon. The research ultimately produced two atomic bombs, which were used on Hiroshima and Nagasaki at the end of the war in August of 1945. While there was a "race" going on between the Allies and Axis powers for the first nuclear weapon, the superior resources and better chemists (Oppenheimer and Einstein are some) allowed the Allies to secure the first atomic bomb and give us an advantage over The Soviet Union at the war's decision with regards to the testing of the atomic bomb.