The Union Day (Romanian: Ziua Unirii) occurring on December 1 held in Alba Iulia, which declared the Union of Transylvania with Romania.
We celebrate this day as the national holiday in ROMANIA

This holiday was set after the 1989 Romanian Revolution and it marks the unification of Transylvania, but also of the provinces of Bessarabia and Bukovina with the Romanian Kingdom, in 1918.

Prior to 1918, the national holiday of Romania was set to be on May 10, which had a double meaning: it was the day on which Carol I set foot on the Romanian soil (in 1866), and it was the day on which the prince ratified the Declaration of Independence (from the Ottoman Empire) in 1877.

This ia an old picture who shows the Union in 1918 in ALBA IULIA

TODAY , we celebrate with parades in all towns , people goes on streets with children to see the show , sing and dance.