UNCOMMON STRUCTURES, UNCONVENTIONAL BUILDERS They are the most remarkable constructions in human history--from the Tower of Babel to China's Great Wall to Machu Picchu--but how and why did they come to be? Here are the answers, entertainingly explained.  UNCOMMON STRUCTURES contains the most amazing, mind-boggling constructions in history. This big, beautiful book features seventeen lively and detailed chronicles of our most ambitious and legendary building projects--the visions and ambition with which they were launched, and the many twists and turns they took as they came into being. Wide-ranging in scope, encompassing a myriad of cultures, time periods and building materials, this lush volume will fascinate general readers, but is substantive enough to hold the interest of architects and designers. Each section is enhanced by a full range of illustrations: color and black-and-white photography, historic drawings and plans, fine art, line art,--the gamut. These are stories of human (and in one case, animal) ingenuity and vision that have inspired and enlighten men and women through the ages.