Here is an actual model of Escher's Ascending & Descending. It measures Height 17.5 inches, Length 24 inches, Width 24 inches. Dave created this model and was the Overall winner in the HADD7 (Hirst Arts Design Derby) contest that recently concluded on August 30, 2006.
You can read exactly how Dave created this masterpiece here.
But this photo is just the surface, the real art is in the interior rooms. Click on any thumbnail image below to see the detail that Dave created. I especially love the caption Dave wrote for the Monk image below.
Great work Dave.
"Please gods, don't make me climb those stairs forever."