Fantasy books that involve voyages on ships

One of my favorite fantasy books as a child was Voyage of the Dawntreader. The adventures and the sense of discovery were fantastic. I eventually ended up reading Earthsea, which I also loved. What other books are there that feature voyages? I would prefer them written for adults. I know about Liveship Traders, but I found Assassin’s Apprentice pretty depressing. So I wasn’t sure I would enjoy it.