Defining the Perfect Block Length for Walkability

The Harvard Gazette spoke with Andres Sevtsuk, assistant professor of urban planning at the Harvard Graduate School of Design, about his research work looking at the connection between block length and what makes a walking-friendly environment. What the research finds is that in terms of a successful community that is pedestrian friendly, having blocks that are too small can prove detrimental.

The smaller your blocks, the more total perimeter you usually have. This perimeter could be activated through retail and commercial facades, and the more of that you have, the more animated or interesting an area tends to be. But if you take that to an extreme and have many tiny blocks, you start spending more time crossing streets instead of actually walking in front of stores. That’s where smaller is no longer better.

So what cities are doing it right? Sevtsuk's research finds that the blocks in Manhattan are very walkable—although, as stated above it involves more than just block size. While Portland, Oregon, Washington, D.C., Minneapolis, and Savannah, Georgia all have short blocks, they don't have the same density of pedestrian friendly destinations and activities that one finds in Manhattan.