Ludlow Tent Colony Site, Labor movement memorial site in Colorado, United States.

The Ludlow Tent Colony Site is a ghost town and National Historic Landmark 18 miles northwest of Trinidad, Colorado, where about 1,200 striking coal miners and their families lived in a tent colony. The site holds the remains of tent platforms and excavated cellar foundations, and is owned by the United Mine Workers of America, which erected a granite monument there.

The 1913–1914 Colorado Coalfield War began with a United Mine Workers of America strike against Colorado Fuel and Iron. About 1,200 miners and families camped at Ludlow, 18 miles northwest of Trinidad. On April 20, 1914, National Guard soldiers and CF&I private guards attacked the colony, killing approximately 21 people, mostly miners' wives and children. The deaths prompted a ten-day retaliatory campaign along a 225-mile front.

The site is owned by the United Mine Workers of America, which erected the granite monument; the names of the dead are inscribed on it. The colony itself was a company-town alternative, home to roughly 1,200 strikers and families. The massacre became a reference point in American labor history, cited by Howard Zinn as the culmination of a violent struggle between corporate power and labor.

The site lies 18 miles (29 km) northwest of Trinidad, Colorado, in open rangeland; the granite monument and the fenced cellar depressions are reached on foot over unpaved, uneven ground. There are no facilities or staffed visitor services, so bring water and sun protection and allow time to walk between the monument and the colony outline.

The site is owned by the United Mine Workers of America, which erected a granite monument to those who died on April 20, 1914. It was designated a National Historic Landmark on January 16, 2009, and dedicated that June 28. Archaeologists have since found evidence supporting the strikers' accounts of the attack.