The architectural gem with golden columns, elaborate moldings and dangling chandeliers was especially vulnerable to fire, as much of the interior is made of wood. The ⁈illion ($19.8 million) renovations included work to move heating installations and electrical circuits outside the building.
Versailles' opera hall was inaugurated in 1770 for the wedding of Marie-Antoinette and the future Louis XVI.
The renovations will allow the hall, which seats 660, to host a more ambitious lineup of concerts and operas.
The program of Monday's inaugural concert featured works by Mozart, Haydn and Gluck.
One upcoming highlight is a Jan. 9 concert by soprano Barbara Hendricks.