It is one of the four towers in the Cuatro Torres Bussines Area (CTBA) in Madrid. The tower is 250 meters high compound of a perfect prism. It goes from a rectangular floor shape to a hexagonal one at the top, so it has four vertical facades, and another four faces moving towards along the entire height.

The lobby and the technical plants are placed in the basement volume and at the top is located the main floor, with an outdoor vertical garden, vegetation and the rest of the plant facilities.

The main facade is formed by a unitized aluminum system consisting of a double skin which interacts with the building’s HVAC system, so it is an active facade. The façade system itself integrates the system of passive protection against fire.

It is a traditional stick curtain wall system, made of lacquered steel structure with a continuous rubber seal, lapped and sealed.

The construction system is the same used in the type facade, but being a single skin because it is an outer-outer enclosure. The whole façade is supported on a lacquered steel frame.