Image of Istanbul, Turkey
Sustainability and climate change
Metropolitan Governance

Marmara Municipalities Union set to host World Metropolitan day 2023 in Istanbul

Marmara Municipalities Union will be hosting this year’s World Metropolitan Day in Istanbul, exploring The Power of Nature in our Metropolises.

This year, World Metropolitan Day will be hosted by Marmara Municipalities Union in Europe’s largest city: Istanbul. The theme for 2023 is “The Power of Nature in our Metropolises,” highlighting the urgent need to improve metropolitan quality of life by bringing nature back into urban spaces.

World Metropolitan Day is a call to rethink the future of cities. In less than three decades, urban areas will be home to nearly double the population they are today. We need to rise to this challenge by making metropolises more liveable, resilient and prepared to support their future communities.

Our hosts

Marmara Municipalities Union (MMU) is the largest regional Local Government Association in Turkey—home to about one third of the country’s population. World Metropolitan Day 2023 will be hosted in the framework of the Marmara Urban Forum (MARUF), Turkey’s first national urban forum.

On 7 October, MMU will hold this year's leading event in partnership with Metropolis and UN-Habitat: “Beyond Urban: How Nature can Transform Metropolises,” in Istanbul. The event will put a spotlight on the power of nature in metropolises and discuss what actions can be taken to increase resilience against climate change and natural disasters.


"Recently, two large earthquakes occurred in the southern part of Türkiye and northern Syria. We have seen that unless we are all safe, none of us are safe, and building resilient cities is a priority for all of us.


In the aftermath of these major earthquakes, learning from nature and rebuilding our cities from the dust by embracing nature-based solutions have once again become vital."


M. Cemil Arslan - Secretary General, Marmara Municipalities Union


Our ambitions

Cities are home to 56% of the world's population, but they use more than 75% of natural resources and emit over 70% of global CO2 emissions. Metropolises have a key role in tackling the climate crisis and supporting global conservation efforts by protecting and restoring natural areas within and beyond their boundaries.

Metropolis members have already pledged their commitment to bringing nature back into urban space by joining our “Seeds for Cities” campaign. Our member cities will plant 5,995,686 new trees before our 40th anniversary in 2025 – but we still think we can do more. This World Metropolitan Day, we’ll be calling on more cities to share their commitments to greening their metropolises.

How to get involved

There are many ways to celebrate World Metropolitan Day and make your voice heard:

  • Events: organise a discussion or hold an online panel with guest experts
  • Workshops: prepare a learning activity to spread awareness and share knowledge
  • Masterclasses: open up a class or talk to disseminate knowledge on metropolitan governance
  • Commitments: approve or enact a plan, policy, programme, regulation or project that contributes to achieving more caring metropolises
  • Make some noise using the hashtag #WorldMetropolitanDay on social media! Like and share our posts at @metropolis_org and @UNHABITAT


Write to us at to be part of the campaign.