Changes

Second option is to hitchhike on Slavonska avenija, this way you dont have to take any public transportation. You can stand after the crossroad of Slavonska avenija and Ulica Josipa Marohnića. Many people go towards the highway on this road. We hitchhiked with the sign "Sesvete", got a ride in 15 mins and got dropped at the petrol station right in front of highway ramps in Ivanja Reka. From here we hitchhiked with sign "Varazdin" and got a ride in 15-20 mins and got dropped at the pay tolls towards north.

Note: this (the crossing of Slavonska avenija and Ul. Ulica Josipa Marohnića) seems to be the best and easiest option. Many cars in the direction, there're traffic lights + lot of space for cars to stop. From the central square (Trg bana Josipa Jelačića) you can either walk (southwards, 3km) or take trams 14 (direction ZAPRUĐE) or 17 (direction BORONGAJ) for 15mins till the stop Vjesnik. The stop is near the crossing of Savska cesta and Slavonska avenija, so you have to walk 10min till the spot where Ul. Ulica Josipa Marohnića is. You can hold sign VŽ (Varaždin). Once you get a ride and are on the highway, be sure to get off at the first gas station (OMV, some 20kms from the starting point), because it's also the last one before Varaždin!