This article analyzes the determinants of population change at the municipal level in a region near Madrid that has suffered rural depopulation since the second half of the 20th century. The region has a city, Guadalajara, which gives its name to the administrative area, and which is located near the border with the Madrid region. The impact of the distance to Madrid on population change is analyzed since the metropolitan area of ??the capital of the country has overflowed towards the nearby regions. The region is crossed by one of the main routes of communication in Spain, the Madrid-Barcelona motorway, and the influence of this road on population changes is also studied. The studied area has a significant difference in altitude between north and south that also seems to be key to explain the evolution of the population in recent decades. Finally, it is analyzed whether the evolution in the areas close to the two nuclear power plants in the region has been different from the rest. In order to carry out a better study, three periods are taken, 1960-1996, 1960-2016 and 1996-2016. In this way, the effect that has been able to occur in recent years when part of the population of Madrid began to populate the closest area of ??Guadalajara is separated.