6,000 years ago · approximate date
The first cities
Large settlements grow into the earliest true cities.
In fertile river valleys, villages grew into cities of thousands of people, with shared temples, markets and rulers. Living at that density called for records, and the first accounting marks followed within a few centuries.
- Period
- Quaternary
- Earth's history already passed
- 99.9999 percent
- 4.54 kilometres
- 6 millimetres from the end
- One day
- 23:59:59
- One year
- December 31, 23:59
Source: Smithsonian Institution · Source to be verified