MC Escher Balcony (1945) in Lego:
MC Escher Relativity (1953) in Lego:
MC Escher Belvedere (1958) in Lego:
MC Escher Ascending and Descending (1960) in Lego:
MC Escher Waterfall (1961) in Lego:
I think the originals were made by Andrew Lipson (www.andrewlipson.com), but his website has been down for ages....
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