Some days you probably feel like you need a few extra hours in your commute to keep up with your growing podcast queue. But, for the most part, commuters have historically been willing to travel about 30 minutes to get to and from work. (I spent 22 minutes in a Starbucks drive-thru this morning.) “In 1994, Cesare Marchetti, an Italian physicist, described an idea that has come to be known as the Marchetti Constant. In general, he declared, people have always been willing to commute for about a half-hour, one way, from their homes each day … From ancient Rome to modern Atlanta, the shape of cities has been defined by the technologies that allow commuters to get to work in about 30 minutes.” Jonathan English in CityLab: The Commuting Principle That Shaped Urban History. “To see how, let’s travel back in time by more than 2,000 years, and move towards the present. (This journey will take less than 30 minutes.)”