In 1942, which U.S. city housed the reactor for first artificial nuclear chain reaction?

nope not uncontrolled,, control rods were definitely part of the experiment...all part of the Manhattan project to develope the atomic bomb...the use of graphite bricks to encase the pile made it an especially dirty job.

Buckeyeartist, I do not think so, as a plaque marks the site. The above article implies not.

It was an uncontrolled chain reaction ? So in other words there might have been a crater where Chicago was?