Which boat trip!?


New to this site but I am very curious as to what is the best boat trip that could be done from ICR.
It is my girlfriends 21st and I want it to be very romantic and peaceful, I was thinking of a trip to Rhodes? But still very unsure, she loves to bask in the sun, relax and swim a little, we love nice sights etc too.
Any help would be much appreciated!
Thanks! Cameron.