Red Castle (Assaraya Al-Hamra) of Tripoli - 50 millieme

Issued in the 1960s as part of the postage due (Segnatasse) series of the United Kingdom of Libya, this stamp features the Red Castle (Assaraya Al-Hamra) of Tripoli, one of Libya's most important historical landmarks. Dominating the old city of Tripoli, the fortress has served as an administrative, military, and political center under successive civilizations, including Arab, Ottoman, and Italian rule. As a symbol of Tripoli's long and rich history, the castle occupies a prominent place in Libya's cultural heritage.

By featuring the Red Castle on a postage due stamp, the United Kingdom of Libya combined a practical postal function with a representation of the nation's historical legacy. The issue highlighted the importance of preserving Libya's architectural heritage while reflecting the development and modernization of postal services during the early years of the independent kingdom.