Valladolid rewards slow walking. The colonial centre is compact, the streets quiet, and the most interesting things — old churches, the cenotes, the museum, the small shops on the plaza — are all within twenty minutes on foot. Start at the main plaza, the Cathedral of San Gervasio on its south side, and the Calzada de los Frailes, the postcard street that leads west to the convent. The town is also the best base for visiting Chichen Itza, the great Mayan site forty kilometres west.
Two cenotes — natural sinkholes filled with cool, clear water — are within walking or short driving distance and shouldn't be skipped. Cenote Zací is in the town itself; Cenote Dzitnup is the more spectacular cathedral-like cavern a few kilometres out.