This paper analyzes the performance of a base station layout for a UMTS network in a densely populated city. The study is carried out using snapshot simulations of an actual city (Barcelona, Spain) with specific traffic and propagation profiles. A first layout is proposed in order to guarantee good coverage with a minimum number of base stations. This layout is approached taking into account the link budget analytical calculations and the first simulation results for a single-cell environment. A second layout is then presented in an attempt to solve the problems that arise in the first (e.g. shadows, blind zones, etc.). This is carried out by finely tuning parameters from the first layout, adding new base stations and changing the locations of the existing ones.