Which Historical Event Would You Go Back To Witness?

Seriously though, I was thinking about this, and I'm curious to know when people would go to and witness an event if, say, a TARDIS was accessible to you?

This isn't asking what event you'd change, per say. Just something you'd witness/experience. It can be anything, small or big. It doesn't even technically have to be famous or well known. It can be something as 'small' as just like going back in time to interact with a relative you never got to meet and be as big as like 'go back in time and witness the moon landing' or something.

I'd like to go to ancient Egypt, or to Guatemala or Mexico and see how those ancient civilizations built their pyramids.
I try to not even think too much about this subject because it absolutely kills me not to know HOW. Seriously.

@ taion
That would be super interesting, and now I'm kinda face palming since I hadn't thought about that. It'd definitely be intense.

I'd go to Germany back in 1989 and help take down the Berlin Wall. I think it would be cool to be apart of that.

There are quite a few historical events I would love to witness. Like seeing how Stonehenge was made or anything was made really. Being on the Titanic before it sunk. Meeting a lot of historical figures (mostly the artists.) and watching them. To see how the Wild West was and how the Native Americans lived as well.

I have too many ideas if I had a TARDIS. I'd abuse that power, for sure. I'd like to go to Ancient Greece, mainly Sparta, to see how they acted and to witness it for myself. I'd want to see the Titanic before it sank. I'd want to witness Marilyn Monroe before my own eyes in person. I'd probably also go back in time to watch my favorite bands perform