Another very enjoyable puzzle here, thanks Quinapalus!
I found it quite tough filling the top of the grid and was then left pretty puzzled about how to make any progress on the endgame. I had a couple of extra words wrong though and eventually spotted the start of the message - a very nice finale from there. The unclued rows can be found in the relevant wikipedia page. My only quibble was that the spelling of the location seemed to differ to the one on Wikipedia.
I was impressed by the grid structure given the constraints and thought there were some nice clues.