Operation Big

Shortly after the liberation of Paris it was decided to bomb German nuclear facilities wherever they lay in order to deprive the Soviet Union of their technology and personnel, unless American troops could get to them first.

His team reached Horb three days later and headed for Haigerloch while the French forward troops occupied themselves with looking for members of the Vichy Government twenty miles deeper into Württemberg in the Sigmaringen enclave.

As the engineer troops consolidated the group’s position in the town, the ALSOS team shot open a bolted door sealing the entrance to a cave in the side of a cliff.

Inside, the team found a large chamber and several smaller rooms crammed with instruments, control boxes, and an array of cylinders described by a frightened German technician as a uranium machine.

[2] Three large drums of heavy water, used to control the reaction in the pile, were later found in the laboratory's main chamber[3] and a German scientist told Pash that the reactor's uranium cubes had been concealed beneath hay in a nearby barn.

U.S. and British engineers dismantle the nuclear pile that German scientists had built up under the Uranprojekt program in Haigerloch in April 1945