Drink Dubrovnik water - it is extraordinary, don't buy bottled one (except in restaurants where it may be needed). Eat mussels, they are so fresh and tasty. Admire great views from Srđ. Eat oysters (brought from Peljesac). Visit the Island of Lokrum, spend the whole day there if you can. Lokrum is one of the nicest wedding venues in Dubrovnik
, with at least four separated wedding sites available, either natural or historical.
Walk the city walls. Don't avoid side streets and corners, they are all safe. Try to choose an early flight for your wedding in Croatia and admire Croatian islands from the air. Take a night swim at Banje beach. Drink more wine on Peljesac, visit cellars there. Visit Arboretum at Trsteno (15 km west from Dubrovnik) - if you are a small wedding party you may get married there too.
Go to Peljesac and eat Oysters and Mussels in Mali Ston. Choose to have a wedding lunch instead of a wedding dinner, so you can take a swim afterwards and party (or chillout) in the evening. Take at least one early morning swim (7 am?). Try prsut (tasty smoked ham). Go for at least one concert of Sorkocevic Quartet. Check out Dubrovnik's rooftops while walking the city walls and make sure to visit Lovrijenac
(standalone fort to the NW from the Old Town).
You find yourself walking in the Old City and it's really hot? In less than 2 minutes you may jump into the sea, just go for one of two small Buža exits through the City walls (to the west). Careful on the rocks!