In 1945, a group of disabled veterans returned to Kalamazoo, Michigan to find a city built to exclude them. Every curb was a wall. Every intersection was a dead end. What they did next would reshape the physical landscape of every American city.
[a][a] Margin note
The design problem
Curb cuts seem invisible now. That's exactly the point. The best infrastructure disappears into use. But someone had to fight for every one of those ramps, and the story of how they did it reveals something fundamental about how design decisions cascade through society.
The original curb cut was a solution to a narrow problem: wheelchair users couldn't cross the street. But what happened next is what urbanists now call "the curb-cut effect": a design change meant for a specific group that ends up benefiting nearly everyone.
[b][b] Margin note
Who else uses curb cuts?
Parents with strollers. Delivery workers with hand trucks. Travelers with rolling luggage. Skateboarders. Cyclists. People carrying heavy groceries. The elderly. The temporarily injured.
The lesson is clear: designing for the margins improves conditions at the center. This isn't charity. It's better engineering.
What this tells us about design decisions
Every design choice has a blast radius larger than its intended target. The curb cut is a three-inch piece of concrete that restructured how millions of people move through cities. When we investigate design decisions, we're really investigating power: who gets to move freely, who gets left behind, and who decided.
[c]