The 40-acre parcel comprises the site of the Ludlow tent colony and represents the event known as the Ludlow Massacre.
Listed in the National Register in June 1985, the Ludlow Tent Colony Site further meets National Historic Landmark criteria due to its association with a nationally significant, excessively violent event in American labor history, the Ludlow Massacre. The site also exhibits a high potential to yield information addressing significant research questions and representing data that contribute to our understanding of American labor history and the archaeological analysis of ethnicity and class interaction.
In September 1913, coal miners and their families, evicted from company housing during a strike, moved into the tent colony, a camp established by the United Mine Workers of America. A day-long battle on April 20, 1914 between strikers, company guards, and the Colorado National Guard resulted in several deaths, including two women and eleven children. During the following ten days, miners retaliated in a a campaign that brought additional deaths and damage throughout the southern Colorado coalfield. Federal troops restored order and the strike ended in failure in December 1914. The United Mine Workers acquired and memorialized the site in 1918.