The most compelling day trip from Tehuacan is south into the Tehuacan-Cuicatlán Valley — the UNESCO World Heritage cactus landscape that begins just outside the city. The road toward Zapotitlán Salinas (about 40 km) passes through the heart of the cactus forest, with stops at the village of Zapotitlán and its botanical garden. The Caves of Coxcatlán, where MacNeish conducted his landmark excavations, are accessible from this road and can be visited with local guides.
Puebla (120 km northwest) is the obvious half-day or full-day trip: one of the great colonial cities of Mexico, with a cathedral, the Zócalo, and the Barrio de los Artistas. The journey takes 1.5–2 hours by bus. In the other direction, the road southeast leads into Oaxaca state; San José Miahuatlán and the transition zone between Puebla and Oaxaca landscapes is worth a drive if you have your own vehicle.