Great Photo Collection Of Abandoned Russian Observatories by katie_melange
There are many more photos to be found here
King Christian IX of Denmark with his children, 1903.
From left to right (top): King George of Greece, Queen Alexandra of England, King Frederick VIII of Denmark, Prince Valdemar.
Bottom: Dowager Empress Marie Feodorovna of Russia, King Christian IX of Denmark, Crown Princess Thyra of Hanover.