Port de la Selva is a coastal town in northern Spain, characterized by rocky shorelines made of volcanic matter. Maria Castello Arquitectura designed a residence to complement the environment. The home consists of dual concrete volumes embedded into a hillside. The two square forms extend toward the sea, cantilevering over the ground below. Both units are topped by gravel from the excavation process to further integrate the structure into the natural terrain, while contours in the bedrock form outdoor patios. Internally, a palette of concrete and oak gives the interior a minimalist aesthetic and expansive walls of glazing frame in expansive views of the coastal landscape.