Arrival to Zagreb
Zagreb is connected by daily flights to many European destinations. More information about arrivals by plane, as well as about train and road connections to other European countries and elsewhere can be found at http://www.infozagreb.hr/travel-plan/arrival
Transport from the airport to the city:
From the airport, you can reach the main bus station in 35-40 min by taking the airport shuttle Pleso prijevoz. One way ticket costs 30 HRK and can be bought from the driver. The shuttle timetable and additional information are available at http://www.plesoprijevoz.hr/en/page/timetable. Another option is to use the ZET bus number 290 operating every 35 min on the line Velika Gorica - Zagreb airport - Kvaternik square (see the line map). The ticket costs 12 HRK and can be bought from the driver.
There are several taxi and ride sharing companies operating in Zagreb. You can reach the city center by taking a fixed price ride with one of the following taxi companies: Ekotaksi (100 HRK, ordered by calling 1414 or via app), Cammeo (100 HRK, ordered by calling 1212 or via app) and Uber (95 HRK, ordered through the app). Other taxi companies offer rides priced according to the taxi meter.
You can also check for further transport information on the following link: http://www.zagreb-airport.hr/en/passengers/to-from-the-airport/35 .
Public transport to Mathematics Department, PMF
The bus routes connecting the bus station at Kaptol (near the main cathedral and not far from the main square) with the Department of Mathematics (PMF - Matematički odsjek, Bijenička cesta 30) are: 106, 201, 203, 226, 238. Exit the bus at the first stop following the roundabout at Bijenička cesta. If you miss the bus stop Bijenička, you can also get off at the next one (bus stop Institute Rudjer Bošković).
You can buy tickets for 4 HRK from authorized vendors (including most newsvendors in town), they are valid for 30 min and include transfers in the same direction. You can also buy the ticket from the bus/tram driver, but note that the price is 6 HRK then. In either case, make sure you validate your ticket.
Bus routes connecting Kvaternikov trg with bus stop Bijenicka are: 201 and 204.
Walking directions from the main square (approx 27 min according to google maps) or from the tram stop Gupceva zvijezda (served by tram lines 8 and 14 going direction Mihaljevac) (approx 10 min according to google maps). Note, both walks are relatively steep.