The 24-hour subway system is more than just the cheapest way to navigate New York City, it's the heartbeat ... (MTA), the least popular subway is the D Train, with just 40% of riders feeling ...

The D, N and A trains were ... are at a 12-year high,” NYC Transit President Demetrius Crichlow said in a statement last month as delays hit 16 subway routes in a hellish Friday for commuters.