Lokrum is the island facing Dubrovnik, it’s accessible by a regular boat from Dubrovnik harbor. To access the nudist zone, when the boat drops you off on Lokrum, walk to the southern tip of the island following the coast (so if you face the sea, it’s to your right). You’ll see a sign telling you are arriving to the nudist zone (FKK zone). It’s not really a beach but more rocks to lay on and sun bath. There is an easy access to the sea to go swimming with a ladder. And for the more daring ones there is a cool stop from which you can jump from a top of a cliff down to the water. It’s almost only frequented by gay guys, mostly tourists with a great mix of nationalities. If the heat is too much, you can explore the pine forest, which is also busy with other guys looking for more privacy.