Carnival

We arrived in Venice with little advance warning that we'd be there during carnival. It was fun, crowded and crazy. I'm not someone who likes to wear a costume, but I don't mind when other people do.
It was great, though there are too many people. Venice isn't a big place, but sixty-five thousand people come in on every weekend day during the festivities. It made it difficult to move around, even, in the crowded little streets. Also, there were a lot of drunk American and German kids there for a more New Orleans, Mardi-Gras type experience, which was offputting.
It was still a wonderful time, and it was easy to get excited about the things being worn. The getups ranged from the simple to the extravagant. Some people rent costumes (or just buy a mask) and others arrive in the city with multiple garment bags and a year's worth of planning.
There is some kind of official judging ceremony and a number of balls, but the main point is to walk around and have your picture taken. The costumed people stopped and posed whenever they saw a camera, and there were almost as many photographers in the streets as revelers (though there were way, way more regular tourists than either).
Often, there were whole groups of coordinated outfits, worn by groups of friends or a whole family.
These two little ones were being initiated early.
One interesting thing about the experience: usually, the people in costume don't speak when they are walking around - so it's impossible to know if they are Venetian, Italian, American or something else.
Two gentlemen who were very enthusiastic about having their picture taken.
There's a lamp at the top of the Rialto that was a popular hangout spot after dark. The light was soft and bright enough that flash wasn't necessary and everything was very dramatic. Also, the view helped. I'm not sure if these two were friends or not.
Children also dress up, though they usually are off the streets before dark. It's a similar thing to Halloween, it seems, minus the candy. This little girl was chasing bubbles around in a princess outfit, which was cute.
As the night went on, the costumes and partying got wilder and stranger.