We went to Mljet National Park as a day trip from Dubrovnik. A bus, a ferry and a couple of mountain bikes and we were surrounded by the most beautiful lakes and gorgeous green scenery. This place is stunning. It's also totally worth the pretty steep cycle ride from Polače to get there, as cycling round the lakes was not only super fun but also a great way to take in as much scenery as possible and find the nicest swimming spots! Quite possibly the clearest water I've ever ever swam in!
Photos - mixture of lumix DLSR and iPhone 5 + vsco cam.