Model of a Penrose staircase
1968
1968
1969
1968
1967
1839 (original); circa 1988 (replica)
1967
(1962); 1982
2000-100 BCE
4000-2001 BCE
1967
circa 1969
1969
1968
1967
1967
1968
1967
1969
1969
1969
1968
1968-1969
1980-1950
1967
1990-95
1969
1903 (original); 1982 (model)
1969
1969
1968
1969
1968
1968
1969
1969
1968
1969
1969
1969
1968
1969
1968
1969
1968
1968
1969
1969
1968
1969
1969