The Complutense University of Madrid (Universidad Complutense de Madrid – UCM) is the largest university in Spain, with around 75,000 students. The High Energy Physics Group (Grupo de Altas Energías GAE),belongs to the Department of Fundamental and Thermal Physics and Electronics within the Faculty of Physics. It is one of the founding members of the Unit of Particle Physics and the Cosmos, UPARCOS, of UCM, a research unit created to support the role of Fundamental Physics within the university. The GAE group pioneered the Spanish research activity in the field of Astroparticle Physics, contributing to the construction and exploitation of the HEGRA experiment since 1985, the pioneering gamma ray observatory in Europe.