Angie Schmitt

It's been almost six months since Paris held its big car-free day, a jubilant event that temporarily cleared the air of poisonous diesel emissions and imparted a sense of how great streets could be without the constant roar of motor vehicles.

Here's an interesting way to evaluate how well a street network works for biking. Stephen Tu and Alex Rixey are mapping streets in Montgomery County, Maryland, based on how comfortable riders of different skill levels find them.

Yesterday was national Bike to School Day, an event that shows kids what it's like to power their own way to school. The fact that we have a special day to promote what used to be part of the daily routine for many children also speaks to the way biking and walking have been marginalized on American streets.

Everyone's paying tribute to Jane Jacobs today, on what would be the pioneering urbanist's 100th birthday. Jacobs' classic critique of mid-century American urban planning dogma, The Death and Life of Great American Cities, is probably the most influential book ever written about planning. But her legacy is also contested, and her ideas still go unheeded in most cities. Was she too averse to change? And how do her theories of city-building work in practice?

It's not enough for highway builders to carve out land at great public expense so they can jam more cars into cities. Now they want you to believe their projects are great for the neighborhoods that bear the brunt of the added traffic and pollution.

Right now, the Seattle region is hashing out how to spend $50 billion to expand transit. The project list, known as ST3, is tilted heavily toward the suburbs, not the urban core where ridership would be higher.

They say "what you measure is what you get," and for the first time, the North Central Texas Council of Governments is measuring walking and biking activity in the Dallas region, reports Brandon Formby at the Dallas Morning News' Transportation Blog.

wenty is plenty in Boston, according to its elected officials. The City Council voted unanimously this week to lower the default speed limit on most residential streets to 20 mph -- and not for the first time.

Impermeable surfaces like parking lots are terrible for the environment in several ways, including the water pollution that results when stormwater runoff causes sewer systems to overflow. In Ohio, the state's highest court recently upheld a fee on parking lots to help mitigate the damage to water quality.

Every once in a while you have to step back and gape at the sheer scale of the highway interchanges America has built smack in the middle of our cities.