in Madrid is likely to see these days is a pair of immense office towers standing on either side of the northern entrance to the city. They dominate the skyline from countless angles and can be glimpsed from miles away across Spain's arid central tableland, the rneseta. What makes them remarkable is not so much that they reach 27 stories into the sky but that they tilt precariously toward each other-at angles nearlythreetimesasprecipitousasthe one at which the Tower of Pisa famously leans.
Unlike...