In the oldest part of the Hofsburg Imperial Palace you’ll find perhaps the greatest treasury in the world. It holds gems, crowns, scepters, orbs and regalia collected and hoarded by the Hapsburg Empire over a period of more than 800 years. The items are visually stunning and historically significant. In fact, the actual Imperial Crown of the Holy Roman Empire rests here.
In addition to the worldly mementos of kings, queens and emperors, there's also an ecclesiastical collection which features relics ascribed to various saints.
Prepare to put extra lenses in your pockets as your photo bag will be held at the entrance.
The guards are constantly/annoyingly present everywhere to make sure you don't steal the treasure (from the glass cases??)
Come at 9am, otherwise this small place gets overcrowded.