Sailboats rest at anchor on a glassy Lake Zurich, their bare masts stitching the sky above the waterline while the twin Romanesque towers of the Grossmünster — Zurich's great cathedral, where Zwingli launched the Swiss Reformation — rise timelessly beyond a canopy of overhanging branches. This evocative real-photo black-and-white postcard by Photoglob-Wehrli AG captures Zurich at its most serene, and it carries a deeply personal message: a father named "Papa" writes to his daughter Gitti and her grandmother ("Liebe Oma") to say he's coming by train Sunday morning between 8 and 10 — "if the train isn't late." Postmarked Zurich 2 May 1951, the card also bears the striking commemorative machine cancel marking 600 years of Zurich in the Swiss Confederation (1351–1951), a landmark civic jubilee. A postage-due violet circular stamp (50 Rappen) was applied in Vienna upon delivery, making this a philatelically layered piece.