If you decide to travel via the autopista from Mexico City to Oaxaca, the only place that merits a stop as you speed along is Tehuacán, the source of a good percentage of the bottled mineral water (Peñafiel, now owned by Dr. Pepper Snapple Group) consumed throughout Mexico. It’s the second largest town in the state of Puebla, but despite some rapid development precipitated by the manufacture of stone-washed denim here in the 1990s, it still feels like an old-fashioned spa town: relaxed, easy-paced, temperate in every sense of the word and with a centre full of buildings from the early twentieth century. The tiled, arcade-fronted house on the main plaza, with its Moorish flourishes, was obviously designed with Vichy or Evian in mind and bears a plaque to Señor Don Joaquim Pita, who first put the water here in bottles. Take a look at the underside of the colonnade for highly graphic murals depicting the five regions that make up Tehuacán district. A more pedestrian introduction to the region fills the halls of the Museo del Valle de Tehuacán, in the elegant Ex-Convento de Carmen at Reforma Norte 200, which features a bright tiled dome that dominates the skyline in this part of town. A tiny collection of prehistoric relics shores up the thinly illustrated story of maize in Mesoamerica and particularly in the Tehuacán valley, which was the first place where the crop was truly cultivated (rather than simply harvested) some six or seven thousand years ago – ample evidence that this was one of the earliest settled areas in Mexico.