Which is better to take the train or a plane from D.C. to New York?

That all depends. Better is a relative term, isn’t it? The plane is a little bit faster, but maybe not as much as you might think when you factor in total travel time. The shuttle flights from Reagan National to LaGuardia take about an hour and 15 minutes. Add 45 minutes to the front end for parking and “airport process” and an hour to the back end for the cab ride into Manhattan and the total is about 3 hours. You might want to take into consideration that about 25% of these flights are more than 15 minutes late. In comparison, a regular train runs about 3 hours and 20 minutes and an Acela is about 2 hours and 45 minutes. There is no need to arrive at the station more than 15 minutes early and New York Penn station is in the heart of Manhattan only a 20-minute cab ride from mid-town or Wall Street giving a total travel time of about 3 hours and 20 minutes for the Acela or just shy of 4 hours for a regular train. Trains have roomier seats and a better place to work. On the other hand, if you are prone to motion sickness you might not enjoy being on a moving train for 3 hours vs the plane which is only in the air for about an hour.