Workers lay the dance floor in the opera house in Vienna February 25, 2014. The Opera Ball is opened by the Austrian president and features a musical programme with soloists and artists from the Vienna Philharmonic and State Ballet before the 144 debutants and debutantes lead into the festivities with a Strauss waltz. The traditional ball takes place on February 27, with tickets starting at 250 euros ($340) and a box as much as 18,500 euros ($25,000). Picture taken February 25, 2014. REUTERS/Heinz-Peter Bader (AUSTRIA - Tags: SOCIETY)