Legend has it that the 19th-century Parisian flâneur, determined not to hurry past the delights of the boulevard, would walk with a tortoise on a leash to slow his stride. That image came back to me as my donkey lowered his head for yet another thistle and I paused to take in the panorama while he chewed. In every direction, mountain ridges faded into layers of pale, misty blue. There was nothing to hear but the wind, the sharp whistles of marmots and the laughter of my two small children. I