Princess Margaret's cake was taller than she was. In my experience, elaborate cakes rarely taste good. Fondant is foul.
Not sure if this has been mentioned, buy here's an interesting tidbit (and I wonder for how many of these cakes this is true): Usually, for cakes that big, only a few layers are edible. The rest are constructed to look like cake and decorated to blend. I'm partial to flower toppers and had my own wedding cake modeled after one eaten by the closest thing we Americans have to royalty.
Since attachments no longer work, I'm linking some that were mentioned but no longer visible. Some of these may be new.
Steph and Gui:
Prince Ali/Aly Salman Aga Khan and Rita Hayworth:
closeup of Grace Kelly and Ranier:
Prince Hamzah and Princess Noor of Jordan:
Vickan and Daniel:
Christoph and Adelaide:
Prince Rasheed El Hasan of Jordan and Zeina Shaban:
Haalon and MM:
Pavlos and Marie Chantal:
Princess Xenia (Habsburg) and Alberto Matta Maya:
Felipe and Leti:
Madde and Chris:
Princess Caroline and Stefano Casiraghi:
Juan-Carlos and Sofia:
King Edward VII and Princess Alexandra:
King Constantine and Ann-Marie:
Edward and Sophie:
Princess Victoria (Queen Victoria's daughter) and Fredrik of Prussia:
Martha Louise and Ari Behn: