Construction began last year on The Shard, London’s only skyscraper to hit the 1,000-foot-tall mark. Proposed almost 20 years ago, it’s something of a miracle that this ambitious mix of offices, hotel, and apartments is rising at all, given the numerous political and economic obstacles to building in London’s historic center. Numerous design revisions by architect Renzo Piano have cost this 87-story pyramid of overlapping glass planes a considerable degree of elegance. Get used to it. Rising from London Bridge, a rail station on the south bank of Thames River, it may dominate the skyline for decades.