The city was occupied from the 6th century to the 10th century and today is a UNESCO World Heritage Site.edit Events and FestivalsDay of the DeadAlthough the Day of the Dead is also celebrated in many Latin American countries except Mexico (and also in parts of Europe, Asia and Africa), the Day of the Dead (Spanish: D??a de los Muertos) is most intensily celebrated in Mexciowhere where it is equal