The World Biggest Cuckoo Clock is located in its own house in Triberg, Germany. The construction of the clock was based on 100 year old cuckoo clock, but at a scale of 60 to 1! The cuckoo bird itself measures nearly 14 feet long, and weights an incredible 330 pounds.
Here is a short presentation about the clock and its construction presented by an animatronic clock-seller:
Here is a video of the cuckoo emerging. Clearly the bird isn't entirely traditional and possesses its own animatronic components. As grand as this is, I would have preferred a simple, traditional cuckoo bird.
Here is where you can learn more about the world's biggest cuckoo clock.
[ Thanks Falk! ]