To many, Mexico is a land of beach resorts, cheap tequila, and quickie vacations. But for those of us who crave history and culture, it is the land of the Mayans — who, although their glory days may have ended with the Spanish invasion, are still alive and well and living just as they did for hundreds of years in southern Mexico. Twenty minutes outside of San Cristobal de las Casas, in the highlands of Chiapas, Mexico, is the small town of San Ju…