Tuborgflasken

Built in 1888 for a national exhibition (the Nordic Industrial, Agricultural and Art Exhibition), Tuborgflasken looks, on the outside, like a giant beer bottle standing on the street. But it is actually an observation tower that was once outfitted with an internal elevator, Denmark's first; the elevator has since been replaced by a more maintenance-friendly spiral staircase.

The elevator hasn't been the only thing to go over the years. The outer surface of the tower, originally made out of stretched canvas, has been replaced by fiberglass.

After the exhibition, which was held in Copenhagen, the giant beer bottle was moved to Beach Road in Hellerup, where it still stands. (It was briefly moved to Copenhagen's City Hall in 1988 to celebrate its 100th anniversary.)