At the end of my Horizon cruise, we saw the Aida Luna docked next to us in New York. The view from our ship was meh, but was excellent from the Air & Space Museum we visited after we disembarked.

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When I was cruising the Breakaway, we saw the Carnival Elation docked next to us in Nassau. I took some close-ups so that the internet can find them if it wants to :) ... (click though to see photos)