Trivia: Which city has the deepest subway system in the world?
Saint Petersburg, Russia
Pyongyang, North Korea
Correct Answer: Pyongyang, North Korea
So why is this answer correct? : The deepest subway in the world is the Pyongyang Metro in North Korea, located 360 feet below ground. An estimated 300,000 to 700,000 people ride the Pyongyang Metro daily, but most of it is closed to foreign visitors.