Mitla [1] (pop. 15,000), although famous, is a quiet town where tranquility is disturbed only by occasional tourist buses along its dusty, sun-drenched main street. A major exception occurs during Mitla’s key fiesta, which centers on the town’s venerable 16th-century church, dedicated to San Pablo Apóstol (St. Paul the Apostle).
If you plan your visit during the eight days climaxing around January 25 (or also around June 29, the day of San Pablo and San Pedro), you can join with the townsfolk as they celebrate their patrón with masses, processions, a feast, fireworks, jaripeo (bull roping and riding), and dancing.
Links:
[1] http://www.moon.com/destinations/oaxaca/the-oaxaca-valley/east-the-textile-route/mitla-archaeological-zone