The history of the discovery and exploration of the site is told through the accounts of various travelers who visited it from the 19th century onward, including Guillermo Dupaix, J.B. Carriedo, Johann von Müller, Désiré Charnay, and A.F. Bandelier, among others. This section also highlights the early 20th-century explorations by Leopoldo Batres and the work of Alfonso Caso starting in 1931, as well as special archaeological projects carried out between 1992 and 1994.