The Moscow Kremlin Egg (1906)

At 36 centimetres, this is the largest of all the Imperial eggs, and Faberge used the extra scale to attempt something closer to architecture than jewelry: a detailed replica of the Cathedral of the Assumption inside the Moscow Kremlin, golden domes and all, with a music box hidden inside that plays two Easter hymns. It's less a surprise-inside-a-shell than the earlier eggs and more a standalone sculpture that happens to open -- the most ambitious single object Faberge's workshop ever built for the Tsars.