So what is a Folly, exactly?
Here’s what Britannica says:
(from French folie, “foolishness”), also called Eyecatcher, in architecture, a costly, generally nonfunctional building that was erected to enhance a natural landscape. Follies first gained popularity in England, and they were particularly in vogue during the 18th and early 19th centuries, when landscape design was dominated by the tenets of Romanticism. Thus, depending on the designer’s or owner’s tastes, a folly might be constructed to resemble a medieval tower, a ruined castle overgrown with vines, or a crumbling Classical temple complete with fallen, eroded columns.
Here’s a great explanation from Dave Delcambre (http://ncartblog.org/?p=535):
Nowhere in the world of architecture does idealism spread its wings more than in the folly. The very etymological roots of the word will tell you so. As related to architecture, the word has been dated from the 1650′s denoting “a sense of costly structure considered to have shown folly in the builder.” One dictionary defines it as “a whimsical or extravagant structure built to serve as a conversation piece, lend interest to a view, commemorate a person or event, etc.: found esp. in England in the 18th century.” So there’s a long history here of architecture for architecture’s sake.
Generally follies are small structures largely devoid of functionality (other than an aesthetic one or perhaps as a brief respite spot at best) but they certainly are not lacking in character, ambition or attention to detail. They are often, in fact, examples of quite compulsive construction behavior. Since follies generally embody the highly personal, even obsessive views of their designers but are largely constructed for no other reason than their own realization, they also reside somewhere in the netherworld between the pragmatic concerns of architecture and the aesthetic priorities of sculpture. Functionality or allusion to specific architectural use is often but a guise for a structure that exists to primarily support philosophical design concerns. Of course when architecture is relieved of functional requirements and the burdens of client demands, it can also revel in something it usually doesn’t get to do: simply be fun and self-indulgent, existing for no other reason than the fact it simply can.
Here are some interesting follies recently seen on Dezeen:
A nice wooden Berliner-good taste one by Baumhauer:
A lovely laminated timber one by architecture students Wing Yi Hui and Lap Ming Wong:
And an absolutely nutty one in true mad-folly taste by Anish Kapoor: