Massive star formation takes place in the dense cores of molecular clouds where the stars may be obscured at optical wavelengths. An excellent signpost of a massive young stellar object is the presence of an ultra-compact HII region, which is a dense photo-ionised cocoon of gas surrounding the newly formed star. UC H II regions are characterised by a far-infrared spectrum produced by the circumstellar dust heated by the absorbed stellar radiation and the shapes of their spectral energy distribution are remarkably similar between sources. Massive stars are responsible for the disruption of giant molecular clouds and trigger further star formation before exploding as supernovae. Issues like birth rates of neutron stars, the number of supernova remnants and the evolution of the ISM are strongly related to the formation and evolution of these objects. They also seem to trace the spiral structure of the Galaxy, defining its morphology. Therefore, it is of fundamental importance to know their number, birth rate and distribution in the Galaxy. The model which I developed consists of distributing synthetic sources, with determined spectral energy distribution and physical size, within the simulated Galaxy and produce the output of an observation of a region of the sky. The first results presented here are estimates of the total number of High-mass star forming regions, their distribution in the Galaxy, and how many will be detected during the SCUBA-2 (SASSy, JPS) and Herschel (Hi-GAL) large scale observational surveys.