- Historical Timeline
Jefferson County has a history rich in people, events and progress. Our historical timeline documents those events, those big, small, important, tragic, and some just plain fun.
Discover the earliest history of Jefferson County from the discovery of gold to the establishment of a provisional Jefferson Territory government.
During the 1860s, Jefferson County opened its first school, endured windstorms, floods and a plague of locusts, and entertained General Ulysses S. Grant on his visit to Golden City.
Find more information on the 1870s in Jefferson County when the Colorado Central Railroad line from Denver to Golden was completed, the first town plat of Arvada was filed, Coors Brewery was founded and telephone service was started.
The 1880s saw the formation of new schools, new communities, business changes and a magnitude 6.2 earthquake.
Learn more about the biggest events of the 1890s such as the opening of the "New City of the Dead," several floods, the first female elected official and the first female graduate of the Colorado School of Mines.
Expansion, industry, municipal incorporations and growth all characterize the 1900s in Jefferson County.
The 1910s saw the Leyden Coal Mine Disaster, the opening of two funiculars, the development of Tiny Town, the Spanish influenza epidemic and a blizzard that dumped the largest amount of snow on record!
Learn about the rowdy 1920s in Jefferson County encompassing the Satanic Coal Mine disaster, first public gathering of the KKK, first female newspaper editor and so much more.
Browse historical events such as fires, floods, the end of prohibition and Depression-era federal works projects in the 1930s.
Construction of US Highway 6, the Golden Post Office and other buildings as well as notable deaths, business openings and other events all mark progress in the 1940s for Jefferson County.
Many notable events occurred in Jefferson County in the 1950s such as the Golden Hill Climb, groundbreaking for the Rocky Flats Nuclear Weapons Plant, the first television sets sold and the grand opening of the first air conditioned shopping center.
Broomfield, Wheat Ridge and Lakewood are all incorporated, Blaster becomes the mascot of the School of Mines and the Beatles perform at Red Rocks. Find out more about these and other interesting facts of the 1960s.
Jefferson County encountered turmoil, prosperity, business development, and many other events during the 1970s.
Read more about the 1980s in Jefferson County, including Tiny Town re-opening, closing and re-opening, the establishment of a K-9 unit at the Sheriff's Office, and completion of buildings on the government center campus.
View events that happened in the 1990s such as the Buffalo Creek wildfire and flood, completion of C-470, listings in the National Historic Register, G-8 Summit leaders visit, and the end of the last working clay mine.
Explore events of the 2000s, like the Hi-Meadow and Hayman fires, the second largest snowstorm on record, the opening of Colorado Mills and many other happenings.
In the 2010s, Jefferson County saw it's first hospital in 100 years, buried a time capsule, celebrated several anniversaries, and survived natural disasters.
Historical chronology of events of the 2020s