Rotunda

So instead, let's just move on to the staircase that sits between the library and the treasure room, which will take you up to the next level, level four.

And on this level, the first things you encounter are the Round Hall, sometimes called the Rotunda, and the Hall of Columns.

Now, the Round Hall is not surprisingly a circular room located above the treasury, and again, we're still in this sort of ancient Roman superstructure.

And this is traditionally believed to be the site of the first chapel constructed here that was dedicated to the Archangel Michael.

And this space now houses the original metal armature of the current Michael statue that sits on the top when that was replaced during a restoration project in the 1980s.

It also seems that the Rotunda and the room below it, the treasure room, were once one room in the Roman period, and that the ceiling/floor that now separates them is much later.

And again, that just emphasizes how important [laughs] that treasury room was in the Roman structure, even though we have no idea what it was for.

There are scholars who suggest that this is where Hadrian's ashes were kept.