What happened at Urban 20 in Johannesburg?
From Johannesburg to the world, here’s how cities drove the U20 agenda. The Urban 20 (U20) Summit concluded on...
Celebrating the winners of the fourth Students Reinventing Cities competition
C40’s global design challenge, Students Reinventing Cities, celebrates the winning projects from this year’s 11 participating cities: Amman, Barcelona, Freetown,...
The City of Johannesburg takes a stand for clean air
On 28 June, the City of Johannesburg and Breathe Cities hosted the Pause and Breathe campaign, featuring the flagship ‘Hike...
How London’s Green Economy Design Lab is supporting construction businesses to strengthen and diversify their workforces
London’s Green Economy Design Lab is helping close green skills gaps and building diverse workforces to meet city clean construction…
A look back at London Climate Action Week 2025
Turning climate ambition into reality Across the world, cities and their mayors are driving climate solutions forward. At a time...
20 Years of C40 Cities: Local Leadership Driving Global Climate Action
From London in 2005 to 97 of the world’s largest cities in 2025, C40 Cities marks two decades of unwavering...