On 10-14 July 2023, the first Joint Summer School of AI-OBSERVER project was successfully held at ERATOSTHENES Centre of Excellence premises in Limassol. During the summer school, very interesting topics were covered, including the use of Artificial Intelligence and Earth Observation for various applications such as: deforestation, flood detection, natural hazards management, feature extraction, data fusion, fire scar segmentation, and many others. Furthermore, Prof. Fabio Del Frate and researchers from University of Rome Tor Vergata, Dr Gerd Reis from DFKI, and PhD students from ERATOSTHENES Centre of Excellence had the opportunity to present their work and discuss with our advanced partners ways to overcome specific problems, and ways to collaborate towards joint publications.