Of course, the first reason is because of Otakon itself, which has had a paid attendance of over 20,000 for the past four years and will almost certainly will again this year (let’s go for 25,000 this year, since con attendance seems to be increasing generally).
However, that is not the only thing going on that weekend.
Second, The Virgin Mobile Festival is being held at Pimlico race track August 9th and 10th. Luckily it’s something like 4 or 5 miles from the harbor area, but that still means a lot of people (It had an attendance of 42,000 on it’s biggest day and 74,000 over two days, though many of those are repeats I’d imagine).
To just pile on, they are commissioning the $1.3 billion destroyer USS Sterett on August 9th, and that’s expected to bring 5,000 people – and that’s happening right there in the harbor area next to the USS Constellation.
So all-in-all, August 9th, which is a Saturday, could see something like 100,000 people hovering around Baltimore.
If anything, I’m just interested to see what’ll happen when some navy admiral passes someone cosplaying as Yoko or something.