Princess Charlene was photographed touring the palace on Wednesday, and posed with a few unsuspecting but happily surprised tourists.
The palace opened to tourists on 1 July, coinciding with the opening of the ornate apartments, Throne Room ,and impressive Hercules Gallery overlooking the Court of Honor, transformed with restored artworks following a 2015 renovation commissioned by Prince Albert.
During the eight-year labour-intensive renovation, People reports, an electrician also accidentally uncovered a large fresco above one hall that had been hidden for centuries behind a false ceiling!
The paintings depict the Twelve Labors of Hercules and are believed to date all the way back to the 16th century.
Charlene, after bumping into tourists seeing the display for the first time ever, was all smiles as she joined their tour.
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