World Mayors Summit Day 2
Cooler cities, transformed food systems, and climate-focused urban planning. At the 2025 World Mayors Summit, C40 Cities announced three new...
World Mayors Summit Day 1
The World Mayors Summit 2025 opened with a powerful plenary as the Mayors of London, Freetown, and Rio de Janeiro...
The Yearly Offer of Action 2025
To deliver the Decade of Acceleration called for by the United Nations Secretary General, decision-makers need to act now, not…
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,...
C40 2024 Annual Report: How cities are building fairer, safer and greener communities
C40's 2024 annual report is here. Read the foreword written by co-chairs Mayor of London Sadiq Khan and Mayor of…
International Women’s Day – Accelerating climate action
From leading the way as the first female mayors of their cities to playing key roles in reforming climate policy,…