This is a long time announced joint issue, postponed several times, but only recently proven to be part of a twin issue, when the Italian stamps’ designs became available. The stamps involving Slovenia and Italy were originally planned to be issued on April 28, 2024, then postponed to January 25, 2025, before finally being issued on February 6, 2025.

Nova Gorica is a town in western Slovenia, on the border with Italy, created through the 1947 Paris Peace Treaty that established a new border between Yugoslavia and Italy, leaving nearby Gorizia outside the borders of Yugoslavia. Hence, Gorizia is the older part of the city, located now in Italy. Both cities have been designed Capital City of the Culture 2025, celebrated by this joint issue. Both countries have issued a souvenir sheet with two stamps showing each one city with, for Gorizia, an aerial view of the Castle, a fortification dating back to the 9^th century, built on the hill overlooking the city, and, for Nova Gorica, the facade of the Palazzo della Stazione, the oldest public building in the city that stands out on Piazza Europa, built in 1906 for military purposes on the Vienna-Trieste railway line.