We believe that a comprehensive aproach to the natural bay of Pasaia, in northern Spain, can't be done without understanding its landscape. Its topography has configured the place during centuries creating a cove behind mounts Ulía and Jaizkibel and connecting it to the sea by the channel between them. The union between landscape and history in this place is absolute. Therefore, our proposal is to recover a view of the landscape in all its dimensions and, endowing ourselves with this instrument, reveal its hidden attributes. The Landscape Catalyst will be a series of small interventions all along mount Ulía that will configure our view and experience.