Vienna to Croatia and Plitvice vs Krka

You're looking into flights so many months in advance that I would not hold the $337 USD figure as a given. It seems really high to me, but very typical of what happens when one looks at flights so far into the future. In other words, I would leave yourself the option of that fare coming down and not making concrete decisions this early. If Croatia Air is the only airline with no competition on that route, then maybe the fare won't go down to budget levels (although I still think it will come down especially given it's for September).

I've never been to either park so can only offer advice on the islands. I went to Brac, which was very mellow and not as touristy or overhyped as Hvar. I really enjoyed it. There was a bus and scooter option around the island but I stayed near the ferry landing in Supetar. The island had a real family feel to it. The beach in Bol (accessible by bus from Supetar) was beyond gorgeous. I also loved Korcula but I took a a day-trip tour there through Viator (you can ferry over but the ferry schedule was too infrequent at the time I visited).

If you like to hike, consider Mljet which is also a park and its own island. The only barrier may be the ferry schedule, unless you're staying overnight. Check out a Croatia Rough Guide or other guidebook for more info.

The difference in driving time from Zadar to Plitvice vs. Krka is estimated by Via Michelin at about 65 minutes. If you opted for the more coastal route to Krka, there would be very little difference.

Your son's very positive first-hand report about Krka is encouraging.

Did your son do both? I confess we only did Plitvice and I am not familiar with Krka. We did Plitvice in September of 2017. ( the same time of year you are doing it) I am glad I went since it was something I really wanted to see. However the crowds can trample its charm (we went late in the day but it was still crowded) If you can get the same scenery without the masses....that would be nice. I do wonder whether Krka is the same experience scenery wise. Plitvice is so large and has so much to see and that is what made it unique. Hopefully someone who has done both can contrast them.

Just Google "Plitvice vs Krka" and you'll see TripAdvisor forums and blogs that will help fill in any blanks. I wouldn't solely rely on this forum when there's a larger universe of travelers to pull info/experience from.

We saw Plitvice National Park in the pouring rain and it was magnificent! I found this blog that has discussed the two Parks. http://www.adventurouskate.com/the-waterfalls-of-krka-national-park-croatia/

I don't think you'll be sad about going to either park.
Hvar is very touristy as well as Korcula.

Look for others and be warned the beaches are not sand but pebbles. The water is oh so blue! Enjoy!

You folks have been so helpful we have decided to skip Zagreb and Plitvice and head directly on the cheap fight to Zadar, which is very early so gets up there by 7:15AM so plan to rent a car and head to Krka for the morning then eat lunch and spend afternoon in Sibenik, driving to Trogir for quick stop on way to Split for the evening.
The Plitvice vs Krka comparison became a wash after reading blogs above so felt we would stay close to the coast as the rest on our trip will mainly be there and minimal driving. Google maps has the entire drive above as less than 3 hours.

Please provide feedback for what we plan for the rest of the trip.

Day 1, Sept 9, is above, sleep in Split
Day 2, Sept 10, stay in Split and check it out but keep the car and sleep again in SPlit then
DAy 3, Sept 11, drive to Dubrovnik via the coastline as much as possible, but then we get there when the crowds are there??, stay over night in Dubrovnik and leave car there.
DAy 4, Sept 12, take ferry to Mljet to hike around the island/park all day and at end of the day take ferry to KOrcula
DAy 5, and 6, Sept 13-14, in Korcula, go to beach, bike/ hike the island, kick back, take latest ferry to Brac
DAy 7, Sept 15 all day and night in Brac but need to get back to Split next day to catch either boat or plane to get to ROme where we will spend a few days before flying back on Sept 19.

Should we spend the night on DAy 2 in Split or in the afternoon drive to Dubrovnik to get there later in the day when crowds are low and spend day in Dubrovnik on day 3 away from old town until crowds receded again. Not sure if we do this we will leave Split without enough time to see what needs to be seen.
Our biggest interest in Croatia is to see as much as possible but leave enough time to to kick back (and kicking back for us is hiking, biking or hanging at the beach as those are our biggest hobbies during the summer).

It's too early now, but you should look at the ferry schedules before you finalize any plan (both to confirm whether there are direct links between the places you want to traverse and whether the schedules align with your plan to leave, say, at the end of the day). For example, you may not be able to jump straight from Mjlet to Korcula on the same day because there may not be a direct connection between the two (you may have to backtrack to Split and then take a ferry the next day - it really depends on the exact schedules). I'd be really cautious in assuming any ferry connections/timetables before you know for sure. I found this to be the case when I went to Croatia - I remember there was no way I could just go to Korcula without having to spend the night due to the times the ferry ran. The examples I gave are from memory so may not be accurate, but I learned the hard way not to assume anything beforehand, especially when not traveling in peak season.

I did look at the ferry schedule from Dubrovnik to Split in September and they schedule a stop in Mljet and then later to Korcula so assume we could do it but might need to pay more to stop as opposed to going straight to Korcula. Will not assume the schedule online now will be the exact schedule in 9 months but it looks like it should work

I have one question.. Do either of you like Game of Thrones? Because if you do there is an excellent GoT tour in Split, that will take you to some excellent places (off the beaten track) with dinner included. I highly recommend! Very small international group.

Korcula is very lovely and beautiful, but not nearly as touristy as Split or Dubrovnik. You should like it.

If you are looking for a thrill.. then go to the Buza Bar in Dubrovnik and jump into the Adriatic from the cliffs... if not that, then at least rent a canoe to paddle around Dubrovnik (I wish I had had one more day to do this!)

you are in for a great trip!

Yes national parks are attempting. Train route (Hzpp.hr): Zagreb - Vrhovine (plitvice) - split. From Split you can take tour to Krka. From Split you can reach Korcula island by catamaran (jadrolinija.hr). Where you can also visit national park Mljet.

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