The Gruta das Torres, which is a volcanic cave located on Pico Island in the Azores, was classified as a Regional Natural Monument in 2004.

With the decision to open it to the public it became necessary to construct a building to support visitors, but one which would also protect the skylight of the entrance to the cave. The architectural project sought to simultaneously achieve both aims by means of an undulating stone wall which transformed into an intricate lacework at the point of contact with the building. This provides an entrance of light which is both filtered and continuous, permitting the uniform illumination of the interior and avoiding the necessity for other openings.

With the exception of this wall the building is coated with an impermeable black finish in order to complement the colour and texture of the vitrified lava within the cave.

In the presence of so strong a landscape our aim was to integrate the building, notwithstanding its contemporary design, within the scale, nature and context of its surroundings.