The Guelaguetza, or Los lunes del cerro (Mondays on the Hill) is an annual indigenous cultural event in Mexico that takes place in the city of Oaxaca, capital of the state of Oaxaca, as well as in nearby villages. The celebration centers on traditional dancing in costume in groups, often gender-separated groups, as is traditional, and includes parades complete with indigenous walking bands, native food, and statewide artisanal crafts such as prehispanic-style textiles. Each costume (traje) and dance usually has a local indigenous historical and cultural meaning. Although the celebration is now an important tourist attraction, it also retains deep cultural importance for the peoples of the state and is important for the continuing survival of these cultures.
The celebration takes place on consecutive Mondays at the end of July in towns around the state and in the capital city's open-air amphitheater built into the "Cerro del Fortín", a hill that overlooks central Oaxaca City. The word Guelaguetza comes from the Zapotec language and is usually interpreted as the "reciprocal exchanges of gifts and services" in keeping with the importance in indigenous cultures of sharing, reciprocity, and extended community. The Guelaguetza celebration also includes many other side events, including a performance of "Princess Donaji", an epic prehispanic theatrical presentation performed the day before the Guelaguetza itself begins.