Thundering straight at the viewer in a cloud of steam and motion, a streamlined Belgian steam locomotive fills the face of this "Souvenir de Bruxelles" postcard with irresistible industrial drama — and concealed within the card's engine boiler is a die-cut leporello accordion insert that unfolds to reveal miniature black-and-white views of Brussels' grandest monuments. The concertina booklet, sliding from the boiler's die-cut slot, displays the Hôtel de Ville, Palais du Roi, Place de Brouckère, Manneken-Pis, Cathédrale Saints-Michel-et-Gudule, and Palais du Roi (exterior), offering a compact guided tour of the Belgian capital that a traveler named something like "Henri" or "Marie" might have slipped into an envelope for family back home. The locomotive illustration — bold, graphic, almost poster-like in its frontality — reflects the Streamline Moderne aesthetic of the 1930s and the pride Belgium took in its railway network, host to the storied Fleche d'Or (Golden Arrow) and Trans-Europ Express routes. This is a premium novelty souvenir piece combining transportation iconography, city views, and mechanical ingenuity into one compact card — exactly what Brussels' busy Gare du Midi gift kiosks stocked for international travelers.