If the idea of searching for buried loot has always appealed to you, there’s no need to wait until a mysterious pirate map falls into your hands while cleaning out the attic. (We can’t all be Goonies.

“Wait!” warns Pier Paolo Perrone in a loud whisper as I reach for a shiny clue at the base of a deep-purple plum tree. He nods toward a gray-haired couple walking past with yoga mats before explaining ...