The architrave popularly called the Gate of the Moon is assigned to Phase 5, the end of the Late SAIS stylistic seriation at Tiahuanaco, by Agüero, Uribe, and Berenguer (2003). Other Phase 5 sculptures are the famous Gate of the Sun and the Llojeta Block.
Isbell, William H.; Uribe, Mauricio I.; Tiballi, Anne; Edward P. Zegarra, 2018, "Visual database", https://doi.org/10.25346/S6/1B33FN.