I haven’t put a jigsaw together since I was a kid. I remember them being a lot of fun, although they rarely had more than a couple of hundred pieces. I’m not sure if I’d ever consider doing one again, but if I did, I think it would have to be this one – assuming I can find a space large enough.
This is Kodak’s “World’s Largest Puzzle“, which is a 51,300 piece jigsaw measuring 8.7 x 1.9m (28.5′ x 6.25′). It’s actually 27 puzzles in one, each featuring different “Wonders from around the world”, but each of those 27 puzzles connects to each other to form the huge overall piece.