Epiphany market is a traditional event that takes place in Rome, in the historical Navona square. NUmerical simulations were used to analyse the crowd dynamics both in normal conditions and in the case of an emergency egress, taking into account the presence of 10000 people. The peculiarity of this project is that Navona square is in the Rome downtown, surrounded by a dense network of small streets, not ideal for the flow of a large number of people in case of an emergency. This required an extensive analysis of all possible scenarios and egress routes optimization.