Billow of black smoke trailing behind her paddlewheel, the gleaming white Köln–Düsseldorfer Rhine steamer surges past the towering basalt cliffs of the Lorelei in this vibrant illustrated souvenir postcard — and tucked inside the ship's hull, a hidden leporello accordion booklet unfolds to reveal seven miniature black-and-white photographs of the Rhine's most legendary landmarks. The concertina insert — visible sliding out of a die-cut slot in the card's lower hull — shows Ruine Drachenfels, Koblenz-Ehrenbreitstein, Schloß Stolzenfels, Loreley, Die Pfalz bei Kaub, Schloß Rheinstein, and Der Mäuseturm bei Bingen, a curated greatest-hits of the Romantic Rhine that generations of German and international tourists treasured. The Köln-Düsseldorfer Deutsche Rheinschiffahrt AG, founded in 1826, was the storied passenger steamship line that operated iconic paddle steamers on the Rhine well into the postwar era; the cheerful banner "Grüß von einer Rheinfahrt" (Greetings from a Rhine journey) above the scene is a classic souvenir formula. The illustrated style, the KD house flag, and the leporello format place this card most likely in the 1930s–1950s range. It is a mechanical novelty postcard — a desirable format among topographical and transportation collectors alike.