The 26th issue of the "Newsletter of Environmental, Disaster, and Crisis Management Strategies", published under the auspices of the Postgraduate Program "Environmental, Disaster and Crisis Management Strategies" of the National and Kapodistrian University of Athens, summarizes the first scientific data and conclusions emerged from the volcanic activity of Cumbre Vieja in the Canary Islands in September-October 2021, including data collected by the Greek scientific mission on the island of La Palma..