Mesa Verde National Park Timeline By sydsearle 550 Ancestral Puebloans Found Mesa Verde 555 They Farmed 1100 They Start Building in the Cliffs 1200 Ancestral Puebloans Left Mesa Verde 1765 Juan Rivera and His Men Saw Ancient "Ruins" Dec 18, 1888 Two Cowboys Found Cliff Palace 1889 The Wetherill Brothers Found 182 Cliff Dwellings Jun 29, 1906 Officially a National Park Aug 2, 2000 Pony Fire Jun 29, 2006 Mesa Verde's 100th Anniversary