"Diffusive shock acceleration operating at expanding supernova remnant shells is by far the most popular model for the origin of galactic cosmic rays. Despite the general consensus received by this model, an unambiguous and conclusive proof of the supernova remnant hypothesis is still missing. In this context, the recent developments in gamma ray astronomy provide us with precious insights into the problem of the origin of galactic cosmic rays, since production of gamma rays is expected both during the acceleration of cosmic rays at supernova remnant shocks and during their subsequent propagation in the interstellar medium. In particular, the recent detection of a number of supernova remnants at TeV energies nicely fits with the model, but it still does not constitute a conclusive proof of it, mainly due to the difficulty of disentangling the hadronic and leptonic contributions to the observed gamma ray emission. The goal of this project is to produce an accurate theoretical prediction of the gamma-ray view of the whole Galaxy at TeV and multi-TeV energies, under the assumption that SNRs are the sources of CRs. Unlike at GeV energies, the diffuse TeV emission from the Galaxy is expected to be more clumpy, showing, on top of a “truly” diffuse emission, extended concentrations around CR sources, especially when they are located close to massive MCs. Predictions will be made for the properties of the clumpy emission, and will include, for example, the number of such clumps detectable by a given telescope, their spectral distribution, and angular extension. When compared with gamma ray-data, such predictions will provide new ways to test the SNR hypothesis for the origin of the CRs up to the energy of the knee."