Osijek has been settled since the Stone Age, when waves of various Central European tribes ebbed and flowed across the plains. Celts, Romans, Croats, Avars, Goths, Hungarians, Austrians, Germans, Slovaks and Serbs have left their traces in the area. In 2007, artifacts from around the region found a new home, diagonally across the Holy Trinity Square from the Museum of Slavonija, in the renovated City Guardhouse and an adjacent house. The Archeological Museum Osijek opened in the fall with a small exhibit in the first three rooms and a display of larger Roman stone artifacts under a glass dome in a lovely arcaded courtyard. Especially interesting is a Celtic helmet that was probably tossed into the Sava during the 1st Century B.C. near Slavonski Brod and recovered during a period when the water level was low. Renovations were completed in March of 2009 and the permanent exhibition, which covers the period from the 5th to the 16th century in now open.

Admission 5 - 10kn. Guided tours 10 - 13kn per person.