Dozens of brilliantly painted trajineras — the iconic flat-bottomed gondolas of Xochimilco — crowd the dock in a riot of floral-arch prows and lacquered red decks, their names spelled out in mosaic tile as tall Lombardy poplars stand sentinel behind a cobalt-blue cantina bearing a vintage Pepsi-Cola sign. This chrome-era postcard captures the "floating gardens" embarcadero at its mid-century tourist peak, just years before Mexico City hosted the 1968 Olympic Games — an event Edna herself mentions on the back, writing to Florence that she "went out and saw the Olympic Stadium — very interesting." Edna reports the trip down took about six hours, that Mexico City's seven million residents live in a breezy highland climate where afternoon showers arrive like clockwork, and that a beautiful "Ballet" that day had been a highlight. The Hilton is comfortable, she assures Florence, and another card is on its way.