I can't find Champion Harbor. I have flew and walked that road the road in Orobas fjords to the end. I went to High Hall and freed the prisoner. But I can't complete Hermosa's quest of returning the necklace because I can't find the guy. I thought I found Champion Harbor. At the end of the road there are a couple of large boats that never move and a merchant Mullet. But I have not found Leon or the rest who is suppose to be in the 'Champion Harbor building'
There's a fish merchant, find him, then look towards the elevator (opposite the boardwalk going to the Slayer camp), walk towards the elevator, then turn left and enter the door.
Basically Champion Harbor is to the right of the High Hall (when facing the hall from the water) - there's a wooden walkway along the shorline that connects the two (they're both within the anti-dragon barrier).
Like the other two have said, all you do is fly around the Fjords and look for an overlapping dragon barrier with a huge citadel inside it and boats in front.
Or: if you find a the Teleporter in High Hall Village (and the High Hall waypoint Scrine is also nearby that teleporter) you can transport quick to Camp Harbour teleporter (where Sepp is) There you can take the elevator down and go inside Champion Harbour
On 7th of february 2015 : I start a new adventure in the Divinity world of Original Sin, it's a Fantastic Freaking Fabulous Funny ... it's my All Time Favorite One !