Taking a sea kayaking tour at sunset is a beautiful way to watch the day turn into night. You will have the chance to swim and snorkel in the Betina cave after spending a few hours paddling around Lokrum island and under the City Walls.
Literally, Bard Mala Bua and Bua Bar are a crack in the wall. Although the drinks are pricey, the views and the ability to jump into the sea at any time make this a cool spot. When it gets dark, they get really crowded, so you should come by at any time.