Above is an image of areas in the Columbia Heights neighborhood in Washington, D.C., specifically at Meridian Street and 14th Street, that are accessible within 15 minutes, thanks to a new mapping tool called Mapnificent, powered by Google Maps. Mapnificent is less of a trip planner and more of a tool for figuring out larger-scale mobility.  You can pick a point on a map and select a time from the point that you could use public transit, walking or biking to get there. For example, the map tells you where you could live or work within a commute of 30 minutes using public transit.

The map seems to accurately depict bus routes that run north-south along 16th Street, 14th Street and Georgia Avenue, but some of the neighborhoods southwest of Columbia Heighbts seem like they would take longer than 15 minutes to reach. What do you think? How accurate is this map? Check out your city. There is probably some variance across cities depending on average headway between buses and trains, as well as the data that the local transit authority provides.

You can also view the maps in color variations that correlate with the estimated time range within the area the map shows. And the map adjusts itself when you check a box for biking. When we did that, the map of D.C. changed dramatically:

For more information, you can watch a few short video tutorials on the program.

Web developer Stefan Wehrmeyer is the mastermind behind the HTML5 and JavaScript program and has recently expanded the map to more than 20 cities. These maps, however, are inherently optimistic in their calculations of timing. Wehrymeyer’s blog explains:

[The map] assumes that you will time your journey in a way that you don’t have to wait for your first transport option. Of course this does not always hold in real life, but it’s a reasonable assumption to work with.

If transport requires a transfer, the program calculates the change in transit by dividing average headway by three, meaning that if buses run every 15 minutes on a certain route, the map would calculate this wait time as five minutes. Wehrmeyer makes this assumption because he figures that most transit agencies link up their various forms of transit in order to reduce waiting times by designing timetables to wait for one another.

Wehrmeyer gets his data from the General Transit Feed Specification (GTFS) Data exchange, which is an aggregator and organizer of data from transit providers. Google specified this format in order to develop its transportation information in Google Maps. The project, according to Wehrmeyer, is inspired by the London-based project still in the beta testing phase, Mapumental.

You can let Wehrmeyer know how accurate his work is by simply going to the Mapnificent site and clicking “Give Feedback.”