Protect your great works and artifacts!

I was just playing as Brazil and had lots of tourism. Russia captured my 2nd best city that was full of great works and artifacts. I captured the city back, but all my great works and artifacts are gone. Russia must have stolen them and put them in their cities (or maybe they all got destroyed?). If I capture Russia's cities then I might be able to get them back, unless if they were traded.

The worst part about it is I could have moved my great works to other cities when I saw Sao Paulo was in danger. I just didn't think to do it because I was so focused in on everything else I had to do it slipped my mind. But it's pretty realistic and a tactic in real life. Throughout history people are always trying to protect great works from invading armies.

They don't get destroyed, but the new owner of the city can take them. In one of my last games, Ghandi wouldn't stop sending missionaries to my cities, so I decided to annex his capital to make a point. Once I did, I noticed there was a painting in the city, which I promptly liberated and sent back to Amsterdam.