Murturm observation tower
I saw this in a recent issue of Interior Design magazine. Apparently, the recently completed double-helix Murturm was built on the "no man's land" border between Austria and Yugoslavia that existed during the Cold War.
As a fabricator, I'm quite impressed with the sheer magnitude and geometry of this venture. At the top, you're standing 89' off the ground. Next trip to Europe will include a visit here...