Views Spike on My Photostream - But Why?

I had a pretty big day over on my Flickr Photostream Tuesday, but I'm not sure why.

Total picture views for the day were 162, and that's about 100 more than I get on an average day.

Most of the views yesterday were of pictures I took when we visited the grounds of the former Nazi concentration camp called Auschwitz in Poland. Those were clearly the views that spiked the daily total upward. But why?

Why all the views of Auschwitz on April 13, 2010?

Four guesses:

1. Poland is in the news right now because of the airplane crash that killed its president and other high officials. So...maybe there are people out looking at pictures of Poland and saw my pictures that way? That's a stretch, but maybe.
2. A few of my pictures were posted somewhere without my permission and whomever is looking at those pages online are also clicking through to see my pictures in larger format at my Photostream.
3. Random. As in, for no particular reason there just happened to be a lot of people in the world looking online for pictures of Auschwitz yesterday.
4. There is an anniversary of some sort associated with World War II, the Nazis or the Holocaust that I am not thinking of or don't know about, and that's driving views.

I'm gonna guess that it's either #3 or #4.

If anyone has any other ideas, let me know.