Santo Domingo de Heredia, Costa Rica is a county facing serious risks from natural hazards, specifically flooding, earthquakes, volcanic activity and landslides. In order to inform disaster risk reduction efforts and improve the safety and well-being of local residents, this article assessed these natural hazards using a geographical approach. First, we described the four hazards based on a review of reports from previous emergencies, scientific papers and newspaper articles. Second, we integrated spatial data on each hazard to create a hazard density index for the county at the level of the census unit (n = 140). Results demonstrate that river flooding has caused the most damage of the four hazards in recent times. Both seismic and volcanic risks (specifically ash fall from volcanic eruptions) affect the entire area of Santo Domingo. Landslides have affected localized, settled areas of steep river canyons in the southern part of the county. In general, the highest density of hazards is located in the southern reaches of Santo Domingo. As such, we recommend that local authorities concentrate their management efforts in that area.