Fregatten Jylland is Ebeltoft's headline sight: a huge wooden steam-and-sail frigate from the 1860s, restored and displayed beside the harbour. You can walk the gun decks, see the cramped crew spaces, and get a clear sense of how much timber, rope, and manpower a naval ship once required.
The ship is especially good because it is not just a relic behind glass. The decks feel physical and slightly absurd in scale, and the museum around it gives enough naval history to make the visit work even if you are not a ship person.