Age of the earliest city

Age of the earliest city (6,500 y)

/fact/age-of-the-earliest-city

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Neat Ratios ...

Age of the earliest city (6,500 y)

is 1/10000 of Time since the extinction of dinosaurs (66 million y)...more
is 1/10000 of Time since the end of the Cretaceous geologic period (66 million y)...more
is 1/400 of Age of earliest stone hand axe (2.6 million y)...more
is 1/400 of Time since the end of the Neogene geologic period (2.58 million y)...more
is 2 x Time since the start of the Iron Age (3,200 y)...more
is 2.5 x Time since the birth of Pythagoras (2,590 y)...more
is 40 x Period of Neptune's orbit (164.8 y)...more
is 40 x Time since the publication of Dickens's Tale of Two Cities (160 y)...more
is 40 x Time since the publication of Darwin's On the Origin of Species (160 y)...more

If this was a standard unit ...