Split, Split KaStela Airport (SPU) & Dubrovnik
Split Airport: Located in Kaštela, Split airport is about 30 minutes from the downtown area. It is very small - there is only one runway and 8 gates (2 for Croatian flights and 6 for international flights). There are only about a dozen flights per day, except on Saturdays when the number nearly doubles. To get from the airport to Split, you can take local bus #37 for 15 kn or the Croatian Airlines bus for 30 kn. The local bus will only take you to the bus station in Sukoisan however, which is rather far from Diocletian's Palace. The Croatian Airlines bus drops you off directly next to the Palace but the seats fill up fast. You could also rent a car as there are several car rental companies located at the airport (it is the 2nd largest in Croatia, after all).
When returning a car to the airport, there are no signs telling you where to park so we just parked in the normal parking lot and gave the ticket to the car rental agency and they moved it to the correct lot. If you want to take the Croatian Airlines bus back to the airport, it can be difficult to know when it will leave Split. Supposedly it leaves 90 minutes before scheduled (Croatian Airlines?) flights but there is no schedule posted at the bus stop so you just need to wait in that area to see if the bus shows up. You can always take a taxi as well and I noticed other smaller shuttle buses that went to the airport but they are more expensive. Or you could walk all the way back up to Sukoisan to get the local bus #37 towards Trogir.
The airport itself only has one restaurant, which doesn't open until 7:30pm and it's before security so unless you have a late flight, you won't be able to eat there. There is a cafe both before and after security, but no restaurant after - though the cafe there does sell chips and sandwiches. Shops at the airport take kunas or euros. To check in for flights, you must go to the counter since there are no machines like at other European airports. With the limited flights, the lines are not long at all and going through security takes only a few minutes (usually they only need to use one metal detector).
Ferries to islands: You can take a number of different ferries to get to the islands off the coast. The most popular are Brač, Hvar and Korčula. Jadrolinija is the ferry company and you can find times and prices on their website. We took the ferry from Split to Brač for the day and it took about an hour and cost 28 kn (in the low season). You buy the tickets for Brač (or other local lines) in the small kiosks next to where the Croatian Airlines buses park, then walk all the way down the port to the numbered docks. There is no separate entrance for pedestrians; you just walk on in the same place where the cars drive on. The ferries are quite nice and have a cafe inside, or you can sit outside on the top deck. For longer distances, you buy the tickets at the Jadrolinija office on the port. The ticket office in Supetar, on the island of Brač, is not close to the port at all so make sure you have plenty of time to walk there to buy your return ticket before heading back to the port.
Getting from Split to Dubrovnik: The quickest option is to rent a car and drive up or down the coast (about 3-4 hours depending on if you take the highway for part of the way). We actually rented a car to go from Dubrovnik to Split airport and it cost 100€ from Hertz. In Dubrovnik, the Hertz office is located to the east of the old town on Frana Supila. It is very far from the hotels in Babin Kuk or Lapad!
Slightly longer is the bus, which takes around 4.5-5 hours. We took the bus from Split to Dubrovnik but I wouldn't recommend it if you get motion sickness easily. There are several stops along the way, including 3 stops at bus stations (with public bathrooms since sometimes you cannot use the bathroom on the bus) in Makarska, Ploče, and Metković, but you do have to pay to use their bathrooms (2 or 3 kn). When you buy the ticket at Split's bus station (next to the train station and across from the port - NOT the same area as the Croatian Airlines stop), your seat will be assigned for you. I recommend buying it the day before so you have a chance of sitting in the front and on the right side, so you can see the coast. The website has the timetable, but the price varies according to the time of day. I paid 109 kn for my ticket. Please note that if you have luggage that needs to go under the bus, you will be charged 7 kn for each piece of luggage! So make sure you have extra money ready when you get on the bus. Dubrovnik's bus station is next to the port, but way on the western side of the city, which is far away from the hotels and old town. You can either walk straight to the end of the bay and get on a local bus at a stop there, or there is a local bus stop next to where the bus from Split will drop you off that can take you to the end of the bay if you don't want to walk.
A third option is the Jadrolinija ferry that stops in Stari Grad and Korčula along the way. This is the slowest option, as the ferry takes about 8.5-9 hours to get between Split and Dubrovnik. Sometimes this route is suspended so it is not always an option.
Local bus routes: The local bus company in Split is Promet and in Dubrovnik it is Libertas. You can look at the maps and time tables online, but neither sites are translated into English. I never took a local bus in Split, but in Dubrovnik, it costs 10 kn. You pay on the bus, or at the counter if the bus stop has one and it is open. You can also buy a day pass for 25 kn at the counter. Bus #6 to Babin Kuk-Pile will take you directly to the gate of the old town.
Day Trips: From Split, a good day trip is Trogir. It is a UNESCO World Heritage Site just a few minutes past Split airport. Take local bus #37 to get there from the Sukoisan bus station north of Diocletian Palace. From Dubrovnik, there are lots of great little towns down the coast closer to Montenegro that are worth a visit. The main one is Cavtat and you can take local bus #10 for 12 kn to get there (takes about 45 minutes and runs every half hour or so). The bus leaves from the local bus "station" at the edge of the bay (and NOT at the bus station where the buses from Split arrive), which is really just a parking lot for the orange buses since there is no information desk/counters to buy tickets. You just pay for the ticket when you get on the bus.
My Map of Split:
My Map of Dubrovnik:
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