Two small children sit side-by-side on ancient stone steps in the famous Callejón del Caracol — "Snail's Alley" — one of Guanajuato's most enchanting stepped passages, where centuries-old stone walls rise on either side and bougainvillea spills over terracotta rooflines in a riot of color under a crisp Mexican sky. The winding alley's spiral nickname perfectly suits its tight, cork-screwing path through the colonial silver-mining city's hillside barrios, and this chrome-era card captures the timeless quality of daily life that drew artists and travelers from across the world to Guanajuato in the mid-twentieth century. Distributed through the Restaurant y Miscelánea Casa Valadez, a landmark establishment on Jardín Unión No. 3, these cards were a staple souvenir of the city before it was declared a UNESCO World Heritage Site in 1988.