2175 The oldest preserved standard of length is the foot of a statue of the ruler Gudea of Lagash; it is divided into 16 parts and is 10.41 inches long.
2170 The Sumerians use a 360-day year, 12-month solar calendar along with a 354-day lunar calendar; the calendar has an extra month every eight years to keep it in step with the seasons.
2155 The birth of Nahor, son of Serug (Genesis 11:22)
2150 Eighty bluestones are set up (two circles) at Stonehenge (England)
2150 Queen Semiramis builds a tunnel below the Euphrates River linking the royal palace of Babylon with the Temple of Jupiter.
2126 The birth of Terah, the father of Abram (Genesis 11:24)
2110 Ur-Nammu of Ur unifies Sumer and Akkad
2100 The last dynasty of Sumer is founded by Ur-Nammu
2100 Ur is an empire and Ur-Nammu writes a rule of law (perhaps the first)
2100 Egypt moves south to establish the Middle Kingdom (7th Dynasty)