We study whether local land use policies are modified in response to enhanced demand for building generated by a new highway. We also examine the extent to which this effect affects building activity. We focus on the case of Spain during the last housing boom (1995- 2007). We assembled a new database with information about new highway segments and the modification of the land zoning status in nearby municipalities. The empirical strategy compares the variation in the amount of developable land before-after the construction of the highway in treated municipalities and in control municipalities with similar pre-treatment traits. Our results show that, following the construction of a highway, municipalities converted a huge amount of land from rural to urban uses. We also show that new highways have an impact on building activity.