Constantinople July 1904: French Levant complete stamp set of 15 values on a registered cover to Prince Carol in <a href="https://en.wikipedia.org/wiki/Pele%C8%99_Castle" class="extiw" title="w:Peleș Castle">Peleș Castle</a>, Sinaia. He later became <a href="https://en.wikipedia.org/wiki/Carol_II_of_Romania" class="extiw" title="w:Carol II of Romania">King Carol II of Romania</a> and one of the greatest stamp collectors of all times.
Designed by Luc Olivier Merson (1846-1920) and engraved by Auguste Thévenin (1856-1921)
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