abstract:The Cherenkov Telescope Array or CTA is a project to build a new generation ground-based gamma-ray instrument in the energy range extending from some tens of GeV to above 100 TeV. It is proposed as an open observatory and will consist of two arrays of IACTs, a first array at the northern hemisphere with emphasis on the study of extragalactic objects at the lowest possible energies, and a second array at the southern hemisphere, which is to cover the full energy range and concentrate on galactic sources.