Car Free Day is 22 September.
If you visit the website and pledge in advance that you will eliminate or reduce use of your car on 22 September, then you could win some free stuff.
Note: Even if you are already a car-free commuter, you can still pledge to be car-free on Sept. 22.
As for me, I normally drive my car a few miles to the Dulles North parking lot and take the Loudoun County Bus from there. On 22 September though, I plan to completely eliminate use of my car. I can walk 0.8 miles from my house to catch the Ashburn Farms shuttle bus to Dulles North and then catch the Loudoun County bus in to the Pentagon like I normally do.
Why not? Give it a try!