The Yusupov palace on the Liteiny prospect was built in 1852. Princess Zinaida and her daughter in law Princess Irina turned it into a hospital during the 1st World War. It is used by the former Communist party today. It is one of 7 palaces owned by the family in St Petersburg. ( They owner 43 palaces across Russia at the time of the Revolution.)
The palace contains one of the most beautiful interiors in St Petersburg, and is wonderfully maintained. On the half landing the original owner ( Felix's Grandmother) also named Zinaida, had mirrors built into the walls, which gave her the opportunity to dissapear if the guest coming up the staircase was not welcome. It contains a very beautiful " Blue Room", which is considered one of the best surviving, preserved examples of Rococo design in Russia.