First Sofia Climate Festival 'HEAT FEST' 2026

From 4th of June until 6th of June 2026, the iconic Banski Square in front of the Regional History Museum – Sofia will transform into a stage for ideas, art, urban solutions, and community energy. The first edition of “HEAT FEST” 2026 – Sofia’s Climate Festival, organized by the Sofia Development Association (SDA) and Sofia Municipality, hosted by Oborishte District, will bring together citizens, scientists, artists, and international experts through a rich three-day programme dedicated to the future of the city.

The first edition of the festival focuses on one of the most important topics related to urban climate adaptation – Sofia’s waters. The area around the Central Mineral Baths has been chosen symbolically as a place where the city’s history, collective memory, and thermal heritage meet. At a time of increasingly frequent heatwaves, water and green infrastructure are key to creating a cooler and healthier urban environment.

The official opening will take place on Thursday, June 4, at 11:00 a.m. at Banski Square, featuring a performance by the National Guards Representative Brass Band. The festival will be officially opened by the Mayor of Sofia Municipality Vasil Terziev, representatives of the Bulgarian Ministry of Regional Development and Public Works (within the framework of the Bulgarian Presidency of the EU Strategy for the Danube Region), and Gustav Csomor from the Monitoring Committee of the Interreg Danube Region Programme.

European Commissioner for Environment, Water Resilience and a Competitive Circular Economy Jessika Roswall will travel to Sofia especially for the occasion and will make an official tour of the festival spaces, where she will explore the showcased green solutions.

Visitors will have the opportunity to experience The Sofianer pop-up exhibition, the interactive urban heat guide WATI, first aid and rescue dog demonstrations by the Bulgarian Red Cross, the mobile automatic air quality monitoring station, and Muzeiko’s interactive exhibition. Children can enjoy eco-workshops, the “Chichopey” installation, and storytelling sessions by Sofia Library aboard the special “Fairytale Tram No. 83.” Adult visitors will be invited to join a workshop by Multi Kulti Collective focused on eco-friendly and low-impact alternatives for everyday life. The programme also includes a green market, free seed sharing, a free plant giveaway by SDA (on Saturday), and the clothing swap initiative “Vartodreshka.”

Throughout the three festival days, visitors will be able to explore the festival’s two thematic zones featuring dozens of interactive activities (June 4: 11:00 a.m.–5:00 p.m.; June 5: 1:00 p.m.–5:00 p.m.; June 6: 10:00 a.m.–12:00 p.m.).

'New European Bauhaus' Zone: A space dedicated to sustainable design, architecture, and innovative urban solutions, featuring universities (including UACEG) and cultural organizations.

'The Waters of Sofia' Zone: Dedicated to the city’s rivers, fountains, and lakes and their role in building a greener Sofia, featuring projects by the Bulgarian Biodiversity Foundation, “Green Sofia,” and others.

Below is a map with the different zones:

Alongside the festival, climate challenges will also be discussed at a high expert level. On June 4 at 4:30 p.m. at Sofia Event Center (Paradise Center), as part of the Green Transition Forum, the international roundtable “Be Ready Cooling Cities Roundtable: Urban Heat Islands, Climate Resilience and the Future of Urban Living” will bring together urbanists and speakers from Austria, Slovenia, Czechia, Montenegro, and Bulgaria. 'HEAT FEST' 2026 is part of the European Be Ready project under the Interreg Danube Programme and is a partner event of the European Green Week.

The festival is also part of the programme of the Bulgarian Presidency of the EU Strategy for the Danube Region. With the support of volunteers from Sofia Helpers, the festival aims to become a new urban tradition for Sofia.

You can see the full programme of the festival here.

Digital Spaces Living Lab will present at the festival WATI - Your Personal Heat Guide in the City

WATI guides you via the coolest routes in the city this summer, showing you the local temperature around you in real time. Whether you're walking, running, or commuting, WATI tracks outdoor temperatures, counts your steps, and navigates you along the coolest paths through its paired mobile app, By choosing WATI, you join a global community that collectively gathers temperature data, refines ‘cool route’ algorithms, and supports future urban planning. The app combines street-level user data with urban temperature maps and satellite thermal imaging, building a new, detailed heat map of the city.

WATI (Wearable Ambient Temperature Indicator) and Your Urban Heat Navigator were developed as part of the Royal College of Art Product Design Programme in London, and are currently supported by Digital Spaces Living Lab (via the LLcloud platform) and Meteoblue.

You can learn more about WATI here and see it in action.

WATI will be showcased in Booth 8 of the Festival space on both days (4th and 5th of June 2026) from 1:00pm until 5:00pm.

Admission to all events at Banski Square is free.

Below you can find photos of the festival and the WATI booth.

Sofia Climate Festival 'HEAT FEST' 2026 is organized in partnership with:

Bureau for Integration and Social Innovation, Bulgarian Society for the Protection of Birds (BSPB), The Sofianer, Bulgarian Biodiversity Foundation, Museumko, Multi Kulti Collective, WWF Bulgaria, National Institute of Meteorology and Hydrology (NIMH), International Organization for Migration, Studio Vazel, University of Forestry, Ecopack Bulgaria, Ecobulpack Bulgaria and Bulecopack, Digital Spaces Living Lab, Bulgarian Red Cross (BRC), Merivel Beekeeping Farm, youth community space “Magnet” (Greenpeace Bulgaria), entrepreneurs and local producers, Gradoscope, University of Architecture, Civil Engineering and Geodesy (UACEG), Municipality of Gabrovo, BCause Foundation, JTI, DevHubOne, Sofia Directorate for Fire Safety and Civil Protection, Imp-Act Agency, Cleantech Bulgaria, European Climate Pact Ambassadors, Tsvetelina Ilieva – creator of “Tsvetna Poshta / Dirty Fingers,” Foundation “Koren,” Sofia Library, Municipal Enterprise “Tourism,” Regional History Museum – Sofia, “Regenerati,” children’s choir “Pim Pam,” and “Green Sofia.”