18th
I like how Tom Vanderbilt of Slate compares car parking (and how free parking spots promotes car use) with bike parking, the latter of which certainly has room for improvement especially in the States. I’m surprised the author didn’t mention the art rack initiatives to combine the utility of bike parking with something aesthetic and representative of the neighborhood.
Developers and building owners are often required to provide bike parking next to the street, but employers should go a step further and provide free parking for bicycles indoors or sheltered (such as in a parking garage with the cars) in as convenient and visibly prominent a place as possible to the workplace. The idea is that bikes can be parked away from the elements in a place where they can be seen, not just for security purposes but to remind drivers of transportation options as that walk in. Bicycle parking access and convenience should match if not exceed that for car parking.
Metro’s recent pedestrian/bicycle improvement studies have a lot to do with parking as well because that two-mile zone around a Metro station is a sweet spot for bicyclists and yet so many Metro riders drive that distance to park at the station.