Four O'Clock Factoid is a daily feature on Track Twenty-Nine helping to get you through the workday with a bit of useless knowledge.
The Peachtree Center Station on Atlanta's MARTA system is 120 feet deep. It was carved from solid gneiss. Due to the geology, pressurized air was required to keep the station from collapsing during construction. Workers had to undergo 30 minutes of compression/decompression when entering/leaving the site. It opened September 11, 1982.