Ephemeral Architecture

The Crystal Palace from the great London exhibition of 1851 was a marvel of its time - going from planning to standing in only 9 months...i really wish this architectural oddity/place of wonder was still standing...but alas, it was destroyed by fire in the 1930s. Not that it would have survived the nightmarish blitz of 1940/41, but nevertheless i feel cheated out of an awe-inspiring travel experience by its absence.
Luckily, for those so inclined, similarly ephemeral lodging exists today in both Europe and North America in the form of ice hotels. I'm sure I'll never be able to convince any of my sun-loving friends or family to take a long weekend break in one of these glorious structures (temperatures inside the hotels range from about 23 to 28 degrees Fahrenheit at all times) but at some point I am going to have to give it a whirl.