13th Atsui-machi Summit 2026 to Be Held in Kumagaya on June 20, 2026! Seven Japanese Cities That Recorded the Nation's Highest Temperatures, Including Isezaki and Tanba, to Gather in Kumagaya!

General Incorporated Association Atsui-machi (Headquarters: Tajimi City, Gifu Prefecture; Representative Director: Yuhei Nakajima) will co-host the '13th Atsui-machi Summit 2026' in Kumagaya, Saitama Prefecture, together with the Independent Administrative Corporation Environmental Restoration and Conservation Agency and member cities that have recorded Japan's highest temperatures: Isezaki City (Gunma Prefecture), Tanba City (Hyogo Prefecture), Hamamatsu City (Shizuoka Prefecture), Kumagaya City (Saitama Prefecture), Shimanto City (Kochi Prefecture), Tajimi City (Gifu Prefecture), and Yamagata City (Yamagata Prefecture).

Photo: Workshop session from the previous summit held in Kumagaya

This year, workshops will be conducted on five heatstroke prevention themes, incorporating perspectives from youth to elderly across regions, with presentations on this summer's initiatives.

Japan's highest temperature record was updated after seven years, with Isezaki City recording 41.8°C on August 5, 2025. Additionally, in April 2026, the Japan Meteorological Agency announced that days with maximum temperatures of 40°C or higher would be officially termed 'extreme heat,' drawing increased attention to heat countermeasures.

The 'Atsui-machi Summit,' now in its 13th year, will welcome Isezaki City and Tanba City—both of which recorded Japan's highest temperatures in 2025—joining the five previously participating cities. Together with local youth, businesses, and elderly residents, the summit will discuss the future of heat countermeasures. This year's initiatives will be jointly developed and implemented with the Independent Administrative Corporation Environmental Restoration and Conservation Agency, including information dissemination on heatstroke prevention.

Event Overview

Date: Saturday, June 20, 2026, 13:00–14:30

Venue: PLACE HALL, 6F Asu Kumagaya (2-115 Tsukuba, Kumagaya City, Saitama Prefecture)

Main Program: - Report on Atsui-machi's 2025 activities and 2026 action plan - Introduction of heatstroke prevention case studies from across Japan - Presentations on heatstroke prevention initiatives by theme, followed by a photo session

Organizer: General Incorporated Association Atsui-machi

Co-organizer: Independent Administrative Corporation Environmental Restoration and Conservation Agency

Supporters: Ministry of the Environment, Isezaki City, Gunma Prefecture, Tanba City, Hyogo Prefecture, Kumagaya City, Saitama Prefecture, Tajimi City, Gifu Prefecture, Shimanto City, Kochi Prefecture, Yamagata City, Yamagata Prefecture, Hamamatsu City

◾️ Event Overview

An event where citizen-led organizations from Japan's hottest cities—including Isezaki City (Gunma), which holds the current national heat record, and former record-holders Tanba City (Hyogo), Kumagaya City (Saitama), Hamamatsu City (Shizuoka), Shimanto City (Kochi), Tajimi City (Gifu), and Yamagata City (Yamagata)—come together to discuss summer heat countermeasures.

About General Incorporated Association Atsui-machi

Headquarters: 3-25 Honmachi, Tajimi City, Gifu Prefecture

Established: May 7, 2019

Representative Director: Yuhei Nakajima

Website: https://www.atsui-machi.com/

Mission: 'What we can do to make hot cities better places to live'

Japan's leading heat-resilient cities share experiences and ideas to overcome extreme heat in alignment with the SDGs, aiming to build a sustainable society.

- Create environments where people can live actively

- Build vibrant human relationships

- Develop cities people want to visit

Vision for the Future: 'Make our local communities something we can be proud of'

Outreach: Share heat countermeasures with Japan and the world to achieve a sustainable society

Exchange: Foster connections among heat-resilient cities

Innovation: Transform the image of 'hot cities'

Photos: Past summit in Kumagaya

Workshop initiative presentations

Group photo with children presenting