Fur is a small island in the Limfjord.It is easy to get to, as there is 24/7 ferry service and the whole trip take whole 4 minutes!! You won’t be able to notice the ferry started and you are already there!
Mandø is an island close to Ribe. What makes this island amazing, is that you have to plan a trip there according to the tides. Twice a day it is not possible to get there due to a road being underwater!