Issued by Greece in 1964, this 20-lepta commemorative stamp marks the 100th anniversary of the Union of the Ionian Islands with Greece (1864–1964). The bold central design features a stylized trident, an emblem traditionally associated with the Ionian Sea and Poseidon, rendered in sharp geometric lines typical of mid-century Greek graphic art. The teal-green frame contrasts beautifully with the monochrome trident motif, giving the stamp strong visual depth. Highly sought by collectors of Greek post-WWII issues, historical commemoratives, and symbolic maritime designs.