C40 Cities

Creating a site that reflects the growth of this leading global climate organisation

C40 site Header

Project overview

We began working with global leadership organisation C40 Cities in 2020, helping them to create a new website that much better reflects their growing leadership in the global climate space.

The result is a low carbon (down over 90% from 6.7 to 0.34g), super fast, engaging site that now clearly represents C40 Cities as a prominent voice that links climate change to issues of social, economic and environmental justice.


  • Multi-Language
  • Interactive city map
  • Streamlined architecture and improved search function


CO2 per homepage view


Lighthouse Accessibility score


Page load time


Being a global organisation, it’s essential that C40 Cities’ website is accessible to audiences around the world.

To ensure this, we configured the new site with GTranslate, so it can be translated into the required language from a drop down menu in the header.

Image of C4 Cities website, demonstrating simplicity of drop down language menu option

Interactive city map

The number one page that all site visitors navigate to when landing on c40.org after the Homepage is the page detailing all of the C40 Cities, c40.org/cities.
To make it easy for people to find more information about a specific city, we integrated a custom interactive Google Map, which includes:

  • Custom and different pin icons for cities that are steering committee members
  • Search and custom filters to display cities that are in a certain region and/or have signed a certain declaration. The C40 Cities team can add to, or remove content within any of these filters as needed
  • Dynamic modals with high-level info and a link to individual city pages.

Streamlined architecture and improved search function

With such a wide and varied audience, including political leaders, CEO’s, trade unions, investors, civil society, citizens, media, youth, funders, C40 staff and client organisations, it’s vital that the architecture of the site is streamlined to make it easy for every visitor to the new site can find what they are looking for.

Following an in depth discovery to identify the main audience, the site content was reorganised to make navigation more intuitive, and we updated the search functionality, consolidating and simplifying content structures with filters for topics, type and relevant cities or initiatives.

mage demonstrating C40 Cities website's search function