Hi , we are 5 british and aussie ladies in our late 20's. We have all backpacked round Asia and thought we would try some where new.  we are flying in and out of Dubrovnik and would like to chill out on an island for 3 weeks, top up our tans, have the ocassional night out and dance, but enjoying swimming , water sports and diving. Our partners will be flying out for a long weekend (via dubrovnik) so we need to be easy to reach. Any suggested islands, accomodation, of we could book something before that would be great. Approx how long would the journey fom Dubrovnik take and how much are ferries? any ideas would be fantastic, thank you    

The islands that come directly to my mind when reading your post are Mljet and Korcula, both have regular ferry lines from Dubrovnik.

Mljet is clooser, has a fantastic National Park and a good offer on watersport activities. As for night life i think it is preety slow, but you have several bars and live music (not confirmed) can be found at Hotel Odisej in Pomena (http://www.adriaticluxuryhotels.com/en/hotel-odisej-dubrovnik-mljet/)

Korcula, on the other hand is a bigger island, good night life, various activities and much to see along the island make it a very popular tourist destination. You can find more info at: http://www.korculainfo.com/

For ferry information check out: http://www.dubrovnik-online.net/english/transportation_sea.php

The ferry time from Dubrovnik to the islands depends on the type of ferry you choose, check out the site to see various options.

Another nice island is Lopud, very close to Dubrovnik. More info at: Island Lopud

you also have elafiti islands, Lopud and Sipan that are very nice to visit....but you'll see when you come to dubrovnik....just visit the suggested Jadrolinija's web page for ferry information