Running the Long Road to Clean Air: Medellín’s #Racing4Air Journey

Medellín came alive on the International Day of Clean Air for Blue Skies, September 7, 2025, as more than 27,000 runners filled its streets, turning the city into a moving celebration of clean air. This year’s Medellín Marathon was more than a sporting event, becoming a global platform to spotlight clean air for livable cities. In partnership with the Climate and Clean Air Coalition (CCAC), the marathon embraced the theme #Racing4Air, transforming Medellín’s flagship road race into a call for other cities and regions to act. Among the runners this year was Vincent Hughes, Communications and Media Manager at the Climate and Clean Air Coalition (and avid marathoner), running alongside athletes from over 40 countries around the world.

“Running is about endurance and collective energy, the same qualities we need to tackle air pollution,” Hughes explained. “By running for clean air, we show that protecting our health and climate is a race we can win together - and you really realize how vital clean air is when you’re gasping for it at kilometer 35".

The city was alive with #Racing4Air. Billboards, bus stops, and banners carried the message of clean air. Runners wore t-shirts with calls for clean air, and the start and finish lines were dressed in blue skies imagery. Even the marathon’s beloved flower mascot, a symbol of Medellín’s green rebirth, carried the clean air message, welcoming athletes and spectators alike. Everywhere you looked, the race’s celebration of health and hope for cleaner air filled Medellín’s streets.

Earlier this year, Colombia once again demonstrated leadership on the global stage by hosting the Second WHO Global Conference on Air Pollution and Health. That gathering underscored a simple truth: air pollution and climate change are deeply connected, and tackling them together brings double dividends, protecting human health while slowing dangerous warming.

The Starting Line: Choosing a Different Path

Years ago, Medellín faced some of the worst air quality in Latin America. Pollution hung in its valley like a heavy blanket, fueled by traffic, industry, and open waste burning. Instead of accepting this as the price of growth, the city acted. It expanded electric buses and metro lines, built green corridors that clean and cool the air, and strengthened environmental standards. These early choices were like the first kilometers of a marathon, full of purpose and momentum, but only the beginning of a long and demanding course, and as runners settled into their pace, they were retracing, literally, the journey Medellín itself has been running for years.

Medellín’s transformation is also rooted in its identity as an urban laboratory, a city known for creativity and a willingness to test new ideas. This cultural drive to innovate has shaped everything from mobility to social policy and made it possible to pilot ambitious solutions for cleaner air quickly and at scale.

This transformation was not abstract. It has been driven by committed local leadership. During the marathon weekend, Martina Otto, Head of Secretariat at the CCAC, met with Dr. Eugenio Prieto Soto, Planning Director for the Government of Antioquia, and Dr. Paula Andrea Palacio Salazar, Director of the Aburrá Valley Metropolitan Area (AMVA). Discussions focused on expanding sustainable public transport, protecting and growing Medellín’s green corridors, and strengthening data and enforcement so that progress on clean air can be sustained and scaled. Their work has been central to Medellín’s progress, aligning urban planning with clean mobility, strengthening air quality monitoring and enforcement, and engaging communities to support cleaner choices.

Part of that work could be seen firsthand while riding Medellín’s integrated public transport system, notably the metro and its signature cable cars. These systems are more than transit; they connect hillside neighborhoods long isolated by geography, cut pollution by replacing diesel vehicles, and bring people closer to green spaces. They symbolize the tangible investments making cleaner air and cooler streets possible.

The Climb: Confronting the Hard Miles

Progress was not linear. Extending clean transport into steep hillside neighborhoods required engineering innovation and political stamina. Enforcing air quality standards challenged long-standing practices and demanded sustained public support. As any runner knows, the “middle miles” can test resolve. Medellín pushed through, measuring results and adapting course while keeping the finish line in sight.

While running the race, Hughes reflected that those tough middle kilometers of the marathon felt a lot like the city’s clean air fight. It was long and grinding but fueled by determination and the encouragement of those who believed change could happen.

Momentum: Breathing the Results

The persistence paid off. Fine particle pollution dropped by nearly 40 percent. Average city temperatures cooled by more than 2°C. New public spaces flourished where smog once lingered. Medellín’s integrated public transport, from sleek metro trains to the quiet, efficient Metrocable, became a global symbol of inclusive, low-emission mobility. Even the journey up to the forests of Parque Arví, a vast ecological nature reserve where residents and visitors escape the city’s heat and pollution, now glides above the city in electric cabins, linking communities to green space while cutting emissions.

Like the moment when a runner feels the course begin to slope downward, these results gave Medellín fresh energy and proof that the hard miles were worth it.

Global lessons are clear too. Cities everywhere can act now with proven tools: regulate oil and gas operations to stop methane leaks, cut black carbon from diesel trucks and shipping, capture methane from waste, promote clean cooking and heating, support climate-smart agriculture, and invest in trees and green corridors. These measures bring fast, measurable health benefits and slow warming within years rather than decades.

The Finish Line: Celebration and a Call Forward

Crossing a marathon finish line is powerful but never final, and maintaining fitness takes ongoing effort. Medellín’s achievements are cause for celebration but also a reminder that clean air progress must be sustained and expanded. Leadership, early action, and public engagement turned a city once defined by smog into a model of cleaner, cooler, healthier living, and this transformation can be replicated elsewhere.

The Medellín Marathon proved that determination and creativity can move a city and the world toward cleaner air. For his part, Hughes finished alongside thousands who had pushed through the same long course, a living reminder that lasting clean air progress depends on many working toward one goal.

Medellín’s journey is not perfect and not finished, but it shows that progress can come quickly when communities, leaders, and innovators run together toward the same goal.

Other cities can draw inspiration from Medellín's path and set their own pace for change. The road is challenging, yes, but the finish line is within reach. And beyond it? An even more ambitious race: the one for a truly sustainable future, where every city breathes clean air and every community thrives.

The starting gun has already sounded. The question is: who's ready to run?