The building's location on a steeply sloping site outside the town of Haro led architects Javier Pérez-Herreras and Javier Quintana de Uña of Taller Básico de Arquitectura to base their design on a geological formation, emerging from the hillside.
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"We conceive an architecture dictated by crystallographic laws," said the architects, adding that the suburban milieu of roads and infrastructure influenced the monumental design.
"The daycare centre is conceived as a great rock, a visible structure for that building-less city," they said.
The building's lower level, housing maintenance and service facilities, is largely enclosed in a monolithic slab that rises from the landscape above a nearby road.
Perched on top of the hill with views towards the town, the upper storey features planar surfaces intended to resemble the sharp edges of a fragmented rock.
The angular forms create overhangs and openings that shelter windows and entrances, while a passageway with bare concrete walls and a sloping ceiling leads to the glazed main entrance.
The entrance connects to large hall, around which classrooms, offices, a cafeteria and a multipurpose space are arranged.
Full-height glazing ensures these spaces are filled with natural light that is reflected by the white walls and light-coloured floors.
The classrooms are positioned on either side of the central hall and feature doors integrated into the glazed walls, which open onto external terraces.
Photography is by Pedro Pegenaute.