Previously, Greece's national flag was simply a blue and white cross. The present version of the flag has been used symbolically since 1828, although it did not become Greece's national flag until December 22, 1978. Although Greece's flag has been blue and white since 1822, the tint of blue has never remained consistent. On October 27th, Greece celebrates its official Flag Day. The former land flag (a center white cross on a blue field) may still be seen in the Old Parliament building in Athens, which today houses the National Historical Museum.