Both divisions of the Department of Geology are located in Horvatovac Street in Zagreb, and form part of the Campus of Science and Mathematics.
If you want to arrive to Horvatovac Street by public transport (ZET), you can take a bus from Kaptol (bus lines 106, 201, 226) and Kvaternik Square (lines 201 and 204), and get off at the station in Bijenička Street, near the Faculty of Science or next one, near Ruđer Bošković Institute.
In order to get to the Department of Geology, on Bijenička cesta (at numbers 30 (Mathematics building) and 32 (Physics building)) you need to pass between these two buildings towards the third one, which is the Department of Geophysics building, where the Division of Mineralogy and Petrology (Mineraloško-petrografski zavod in Croatian, or shortly MPZ) is situated on the second floor. The address is Horvatovac 95.
If you continue towards Horvatovac Street, you will reach the Division of Geology and Paleontology (Geološko-paleontološki zavod in Croatian, or shortly GPZ), at the address Horvatovac 102a. The GPZ is located on floors 0 and -1 of the smaller (northern) building, which we share with the Department of Biology.