On December 2, 1942, scientists at the University of Chicago produced the first controlled nuclear chain reaction in human history. Soon after, the reactor was relocated to “Site A” in the Palos Park Forest Preserve where scientists performed experiments and built the additional reactor as part of the Manhattan Project, the U.S. nuclear development program during World War II. When the site closed in 1954, the two reactors were buried and a decades-long environmental clean-up and monitoring effort began. In 1991, after extensive clean-up by the Department of Energy, the area was re-opened for safe public recreation. Today, Red Gate Woods remains the burial site of the world’s first nuclear reactors—marvels of science that ushered America into the Atomic Age.
