Last night at 8:45 pm, the power went out in the Gateway Arch in St. Louis trapping 240 people inside the structure. It took rescue workers 2 1/2 hours to get everybody out, but no one was hurt in the process. 100 people stuck on the observation level were able to exit the Arch down 300 feet of stairs to a freight elevator. The Arch is 630 feet tall. The power loss may have happened when a cable attached to the south tram snapped. Service to the top of the Arch is expected to return today in the north tram.