15. Crystal Palace, London, UK

Sir Joseph Paxton (1803–1865), a self-made botanist, designer, and engineer of greenhouses was the principal designer of the Crystal Palace, the structure inside of which the Great Exhibition of 1851, a world’s fair of technology and production of the times, was held. At the time, this was the largest international exhibition held anywhere. It marked the culmination of an extraordinary confluence of forces emanating from international commerce, technology, architecture, and politics. Its impact on the engineering of buildings, not to mention the architectural world is, surprisingly, remarkable. This design was obtained at the last minute, at a time when all options were practically exhausted. While a design competition, which yielded more than 230 entries, was held in advance, the jury decided to use none of these designs, including that of the winner. As the jury, in a desperate move, was contemplating to assemble a hybrid design from the outstanding features of some of the competition entries, Mr. Paxton was given a chance to submit a design for the building, whose innovative features demonstrated their value until the structure burned down in 1936 as the assumption that glass and iron would be fire proof would not hold true.