Issued in 1937 by the Mozambique Company, this engraved 15 centavos stamp depicts the historic Fortress of São Caetano in Sofala, an important symbol of Portuguese colonial presence along the East African coast. Printed by Waterlow & Sons Ltd. in London, the design combines rich carmine red framing with black engraving to highlight both the architectural strength and the cultural significance of Sofala, once a thriving port and trading hub. This issue formed part of the "Country Symbols" series, celebrating the colonial company's infrastructure and historic landmarks. With a comb perforation of 12½ and produced through fine line engraving, this stamp exemplifies the high production quality associated with Waterlow’s colonial issues of the late interwar period. Comparable examples from the same series are keenly sought after in the philatelic market, especially when tied to historical themes of fortifications and empire. Estimate "$25 – 40". Condition: Postally used with visible cancellation, light handling marks but overall well-preserved for age with strong color and intact perforations.