Programs like Metro’s trip planner can make riding transit easier for new riders and seasoned commuters alike. But the way that trips are shown has a huge impact on the effectiveness of the data.

A few weekends ago, I needed to travel downtown for Transportation Camp. Since I don’t often make the trip, I decided to use Metro’s trip planner to see when I would need to leave in order to get to the event for its 10 am start. The result was not very helpful.



I chose the option to plan a trip arriving by 9:30 to account for trackwork scheduled for the Orange Line and also for the walk to the venue. As you can see, the trip planner told me to expect a travel time of 1 hour and 36 minutes. That’s a long time. A lot longer than it should be, in fact.

The problem lies in the way Metro’s trip planner deals with “arrive by” queries. When users try using the “arrive by” tool, the planner tool gives riders the trip arriving closest to (but not after) the time specified. That sounds good on the surface, but let’s consider my trip.

If you look at the results closely, you’ll see that the trip planner has me wait 40 minutes at New Carrollton station. If I transferred directly from the bus to the Orange Line, I would arrive at Foggy Bottom station at 8:55, which is 35 minutes too early. Instead of telling me this, the planner just makes it look like I have no option but to wait 40 minutes at New Carrollton.

That kind of information can turn riders off. Why take a trip that will take over an hour and half when you could probably drive it in a half hour?

What would be particularly helpful would be to show each possible permutation of a trip, especially when connections are involved. Metro’s trip planner deals with this by returning each as a separate itinerary. For example:

  • Board a bus at 9:10. Exit at the Metro stop at 9:25. Take a Green train at 9:30.
  • Board a bus at 9:10. Exit at the Metro stop at 9:25. Take a Green train at 9:36.
  • Board a bus at 9:10. Exit at the Metro stop at 9:25. Take a Green train at 9:42.


Those aren’t different itineraries. They’re just different waits at the Metro station.

I think a format like this would be more helpful. The trip Metro actually planned for me is outlined in red.


I’ve also included (in yellow highlighting) one arrival after the “arrive by” time. This allows for trips that arrive within a reasonable time. For example, if I want to arrive by 9:30, and there’s a train that gets me there at 9:31, that’s probably okay, and a trip I might want to know about.

Other itineraries should be substantially different from the first (since it’s showing all options). In this example, there’s really only one other feasible option, and that’s to travel by way of the Green Line.


An itinerary like this would allow riders to better plan their trips. Perhaps arriving early isn’t a good option. In that case, they know they have time to stop off for coffee, or perhaps that they could wait for a later bus and still arrive within a reasonable time.

WMATA’s arrive by function used to return all sorts of gibberish to achieve “alternate” itineraries, including trips that went past where you wanted to go and then had you change vehicles and return. These days, Metro has modified their planner so it does better, though it still leaves a lit to be desired.

Metro’s trip planner and other trip planning applications could be better by showing more options. I know my graphics leave a little to be desired, but it’s the principle I’m trying to illustrate.

Do you have thoughts for ways to improve trip planning?

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Matt Johnson has lived in the Washington area since 2007. He has a Master’s in Planning from the University of Maryland and a BS in Public Policy from Georgia Tech. He lives in Greenbelt. He’s a member of the American Institute of Certified Planners. He is a contract employee of the Montgomery County Department of Transportation. His views are his own and do not represent those of his employer.