Climathon (EIT Climate-KIC)
24-48 hour citizen hackathon run by EIT Climate-KIC. Each participating city sets its own local climate challenge; teams of citizens, students, and entrepreneurs develop solutions. Best team in each city receives Climate-KIC coaching post-event. Over 30,000 participants since 2015.
Cities are de facto compared by participation numbers, idea quality, and downstream city implementation. The Climathon Awards single out 'most improved' cities and best-traveling ideas, creating a global city-vs-city showcase. Cities like Vienna gained recognition through outputs like the Urban Heat Vulnerability Map.
Within each city, citizens form teams that collaborate intensely for 24-48 hours, often hosted by city government or universities. Local mentors, businesses, and city officials act as coaches. Strong intra-city collaboration scaffold; winning teams typically continue working together with municipal backing.
Time-boxed civic intensity that explicitly turns city-level participation into both internal collaboration and external reputational comparison. The 'city sets its own challenge' design avoids forcing one-size-fits-all metrics. A transferable lesson for BelongHub.
Others in the same family
Energy Sparks (UK schools energy league)
Open-data platform that ingests half-hourly electricity and gas meter readings for ~620+ schools and turns energy investigations and saving actions into points. Public national, regional (London, North-West England, etc.), Multi-Academy-Trust, and Local Authority scoreboards rank schools in real time across the academic year. Cash prizes for top schools are spent on a sustainability project the school chooses.
2zero Klimathon (Mannheim, Glienicke, Hufeisen-Region, Schleswig-Holstein)
6-week 'Klimathon' run by Berlin-based 2zero (formerly Klimakompass). Each week features 4-6 challenges across themes (mobility, food, energy, consumption, digital, leisure). Mannheim ran as a CoLAB pilot under the EU '100 climate-neutral cities by 2030' Mission starting Jan 2025.
Cool Block / Cool City Challenge (Empowerment Institute)
Five-month, nine-meeting structured program where 5-8 households on a city block work together on carbon reduction, disaster resilience, water stewardship and neighbourhood livability. A city launches a campaign and recruits Cool Block Leaders, who invite neighbours onto a team. Block teams then aggregate into 'Cool Neighbourhoods' of ~10 blocks. Pilot achieved 32% average household carbon reduction and won NASA's outstanding sustainability solution.
Defi Ensemble, on bouge (ParticipACTION Community Challenge)
Every June, Canadian communities (cities, towns, First Nations, rural municipalities) log physical-activity minutes via the ParticipACTION app to compete for the title of 'Canada's Most Active Community' and a CAD $100,000 prize, plus 12 regional prizes ($5k-$10k) for the most active community in each province/territory. Quebec City won the 'most active community in Quebec' prize multiple times. Over $1.5m awarded to 49 communities since 2019; $7.2m in grants for follow-on local sport initiatives.
Cycle September / Love to Ride workplace + city leaderboards
Annual September cycling challenge run by Love to Ride. Riders log trips via app; workplaces compete on regional and global leaderboards segmented by size bracket. In 2023 Philadelphia alone, 412 riders from 56 workplaces logged 4,898 trips.
Klima-Taler
City-branded climate app powered by motiontag that auto-detects walking/cycling/public-transport trips and converts CO2 saved into 'Klima-Taler' coins redeemable at local pools, museums, shops. Each participating city gets its own white-label instance; users join open teams.