 The scientific investigation of Chaco Canyon started when Richard Wetherill began his exploration of the canyon in 1895.Wetherill was well known for his discovery of some of the largest Ancestral Puebloan dwellings in Mesa Verde, and after an invitation from amateur archeologist Sidney Palmer to survey Chaco Canyon, organized a one-month expedition to the region.He secured financial backing for a full season soon afterward, and in 1896 full-scale excavations began at Pueblo Bonito.