Model of a Penrose staircase
1968
1968
1969
1968
1839 (original); circa 1988 (replica)
(1962); 1982
1903 (original); 1982 (model)
2000-100 BCE
4000-2001 BCE
circa 1969
1969
1968
1968
1968
1969
1969
1968
1969
1968
1968
1969
1969
1968
1969
1969
1968
1969
1969
1968
1969
1968
1968
1969
1969
1968
1968
1969
1969
1968
1968
1968-1969
1980-1950
1968
1969
1969
1969
1969
1969
1969
1969
1969