While the leaning form of the control tower sets it apart from typical towers, it does use a tripartite vertical structure, a tradition carried down from Louis Sullivan's high-rise designs in the late 19th century. A light-colored stone defines the first floor and anchors the tower to the ground, a single wall reaching out to indicate the entrance. Above this copper sheets are arranged horizontally using standing seam construction that gives the object a texture from a distance. The top is a glass box behind copper slats, giving the building the image of an abstracted, classical lighthouse.

Lisbon Harbor Control Tower.Lisbon., Portugal