My whole working life I've been a man of the trunk line. Thirty years moving freight — beverages off a dock in the Georgia heat, pallets of everything a growing suburb can want, trucks that don't leave unless the load sheet balances to the pallet. I stood beside the conveyor, watch in hand, learning the one lesson that never leaves you: the trunk line is the easy part. The line between two big hubs runs itself. The hard part, the part that makes or breaks the year, is the last mile — the hills, the stairs, the small docks, the people at the far end nobody's route planner ever counted.
It took me the better part of my career to realize I'd been drawing Medellín all along. That I didn't come all the way from the Andes to Georgia and change trades. I came carrying a city inside me, a city that is the best teacher of supply-chain thinking I ever had — because it had to learn it the hard way, or die.
One. The city that refused to break.
Medellín is the capital of Antioquia, in Colombia's north — la ciudad de la eterna primavera, the city of eternal spring, founded in 1675, tucked into a narrow valley ringed by green mountains. It's beautiful in that way that hurts, and for too long it was also broken in a way that hurt more. Through the eighties and early nineties it was known as the murder capital of the world, the seat of a cartel war that took tens of thousands of lives in the streets of a valley barely wide enough to hold its river. That's the Medellín I grew up hearing about, the one my abuela prayed around.
But cities, like supply chains, decide whether they're going to keep bleeding or start routing around the blockage. And here's the part I hold onto: Medellín didn't fix itself with a single big lever. It rebuilt itself with a thousand small ones, in a sequence, on a schedule — which is exactly what an operations man recognizes as a plan.
Two. The trunk line through the sky.
Here is the fact that pins me to my chair every time I think about it: the first urban transit cableway on earth is not in some sleek European city. It is the Metrocable, in Medellín, part of the city's rapid transit network — gondolas built to carry commuters up the steep hillsides where the poorest barrios sit, the neighborhoods that the flatland and its jobs had always considered unreachable. Built not as a tourist ride but as a trunk line connecting the hills to the valley floor, to the metro, to work.
Fifteen minutes from barrio to metro station. Fifteen minutes that used to be an hour up switchback stairs in the rain, or nothing at all — because for too many families it was nothing at all. When you give a hillside access to the valley's jobs, you're not building infrastructure. You're re-entering a million people into the network that the city runs on. You are, in supply-chain language, opening a route to a market that was stranded by geography.
Three. The frame I've used ever since.
Every distribution center I've run since, I've run on the frame Medellín taught me. There are three rules, and they hold whether the cargo is a pallet of cold drinks or the future of a young person.
Rule one: the last mile is the order qualifier. You can have the fastest trunk in the state and lose on the last mile. Medellín's lesson: reach the stranded endpoint and you win the market nobody else can serve. I tell every junior planner the same thing — stop optimizing the highway, it's already fast. Find the hill nobody else will climb.
Rule two: build the system so access is dignity. A route to jobs isn't charity; it's a transaction. Ownership changes the behavior of everyone in the network. The Metrocable worked because it was real, reliable, and dignified — people rode it not as charity cases but as passengers. When you design a system where the endpoint holds their own stake in it, the whole thing compounds.
Rule three: sequence and schedule beat heroics. Medellín didn't save itself in a sprint. It rebuilt over decades, one line, one library, one public space at a time, in a deliberate sequence. Slow, compounding, on-schedule progress beats one heroic miracle every time — and it's the only kind of progress you can actually scale.
"The trunk line is easy. The last mile is where the money — and the dignity — actually lives."
I think about that on the dock at 4 a.m., when the load sheet doesn't balance and a driver is waiting and the temptation is to cut a corner to hit the clock. I think about the hillside kid who got fifteen minutes back from her day, and what she did with them. And I think about my abuela's prayer, and about how a city's plan and a grandmother's faith turned out to be the same thing: a route out that doesn't make you leave who you are.
The cable car was never for tourists. It was for us — the ones who still believe, every single on-time departure, that the last mile is worth building for.
— Carlos