The past two shots were taken in the privately owned Yusupov Palace in St. Petersburg, Russia. This theatre was also in the massive building! The place is almost beyond comprehension - a family of 4 lived there and they had their own theatre in their own house!! It even had a tiny orchestra pit! It's totally insane!! Apparently it is still used today!! I was standing near the stage looking towards the exit when I took this shot.
If you're interested there's a short you tube video I found that shows the space better than my shot could. You can skip over the ad in the beginning after just a couple of seconds: https://www.youtube.com/watch?v=e8ln7XITq_0