March 6, 1880
North School opens in Golden to alleviate overcrowding at South School. Building demolished in 1965.
May 4, 1880
Adolph Coors buys out his partner Jacob Schueler, becoming the sole proprietor of the Golden Brewery.
July 16, 1881
Colorado State Industrial School, for incorrigible young men between ages 7 through16, later the Lookout Mountain School for Boys and Lookout Mountain Youth Services Center, opens in Golden. (Established by legislation February 12, 1881 by Governor Pitkin.)
Unplatted area comprising Wheat Ridge named by resident Henry Lee, who served as a state senator, 1885 to 1889. The area was first settled as farmsteads in 1859.
November 7, 1882
Election day earthquake of magnitude 6.2, the largest recorded in Jefferson County, shakes Golden, with effect particularly felt at Jefferson County Courthouse.
Colorado School of Mines holds its first formal commencement for two graduates, William B. Middleton and Walter H. Wylie.
September 15, 1883
Sacred Heart College, now Regis University, moves to and opens in Morrison.
- Begun in 1870, the Welch Ditch is completed to carry water from Clear Creek to agricultural lands east of Golden
- Coors Brewery gives people $0.45 for returning a dozen empty quart bottles
Community of Fairmount is established.
Town of Broomfield established; originally called Zang's Spur, the town is located in Adams and Boulder Counties as well as Jefferson County.
December 15, 1887
First electricity in Jefferson County as Golden Illuminating Company’s power plant goes online.
George West's son, Leslie B. West, starts working for the Transcript.
December 11, 1888
Chief Colorow, one of the most familiar Native American inhabitants in Jefferson County, dies of pneumonia at Ouray Agency, Utah.
First international student graduates from the Colorado School of Mines.
May 13, 1889
Edgewater town plat filed.
July 1, 1889
Lakewood town plat filed.
September 9, 1889
White Ash Coal Mine disaster when a tunnel built under Clear Creek in Golden floods, drowning ten men whose bodies were never recovered.