Vasco da Gama Tower in Lisbon

You're standing at the Vasco da Gama Tower, on the north bank of the Tagus, in Parque das Nações in the east of Lisbon. Go on, look up. At around a hundred and sixty metres, the tower is the tallest structure in the city. Notice the shape? The architects, Leonor Janeiro, Nick Jacobs and the firm SOM, took their cue from a caravel, the sailing ship of the great age of discovery. There's a straight mast, and beside it a billowing sail made of metal tubes. Up top, at a hundred and twenty metres, sits a platform meant to be the ship's crow's nest. And down below, the base juts into the river like the bow of a boat.