Palacio Postal

This guide to Palacio Postal in Mexico City opens with an envelope addressed to a street that doesn't exist, one of thousands Mexican children send each December to the Three Kings and Santa Claus from inside this working post office. It follows how the building, a gilded 1907 landmark by architect Adamo Boari, transforms each winter into the Palace of Wishes, and the postal workers who make sure every letter gets an answer. Look up at the grand staircase for frescoes painted over real gold leaf.