Complex sentence: In the summer of 1848, two white marble sculptures of the "Medici lions" were installed on the central staircase leading up to the palace, carried out by the Italian sculptor Giovanni Bonnani.
Split into simpler sentences: In the summer of 1848, white marble sculptures of two "Medici lions" were installed on the central staircase leading up to the castle. The sculptures were carried out by the Italian sculptor Giovanni Bonnani.