2015 starts with the "Life Ball" under the motto "Gold". (Picture: Jürgen Hammerschmid, Inge Prader)

VIENNA (AP) — Vienna's central City Hall Square was

transformed Saturday into a mythical world of

pagan rites and fantastic spectacle as the city hosted

its biggest annual party of the year.

The occasion, Europe's biggest charity event, was

serious: raising money for AIDS and HIV research.

But as in previous years, the 23rd Life Ball was also a

free-for all gala with an emphasis on diversity.

Prince Harry’s award will be announced at The Life Ball, pictured, which is the biggest charity event in Europe supporting people with HIV or AIDS.

Vienna's central City Hall Square was transformed into a mythical world of pagan rites and fantastic spectacle as the city hosted its biggest annual party of the year. The occasion, Europe's biggest charity event, was serious: raising money for AIDS and HIV research. But as in previous years, the 23rd Life Ball was also a free-for all gala with an emphasis on diversity.Picture: AP Photo/Herwig Prammer

(AP Photo/Herwig Prammer)

Conchita Wurst is the face of the 2015 Lifeball and is been featured in the official Lifeball 2015

US model Yasmine Petty, left, arrives for the largest annual AIDS charity gala in Europe known as the Life Ball, at the Vienna International Airport near Schwechat, Austria, Friday, May 15, 2015. (AP Photo/Ronald Zak)

Gery Keszler, organizer of Life Ball or Party for Life, the primary philanthropic activity in Europe to raise resources for HIV and AIDS research, accompanied by the artist after American genre Amanda Lepore, at the international airport of Vienna in Austria, Friday May 15, 2015. The Life Ball on Saturday. (AP Photo / Ronald Zak)

The Life Ball is one of the biggest AIDS charity events in the world. (Picture: Jürgen Hammerschmid, Inge Prader)

Austrian singer and European Song Contest winner 2014 Conchita Wurst, enter, performs on stage during the opening ceremony of the Life Ball in front of City Hall in Vienna, Austria, Saturday, May 16, 2015. The Life Ball is a charity gala to raise money for people living with HIV and AIDS. (AP Photo/Herwig Prammer)

Artists take a photo after arriving at the opening ceremony of the 23rd Life Ball in Vienna on May 16, 2015 (AFP Photo/Christian Bruna)

A model presents couture by Jean Paul Gaultier during a fashion show at the opening ceremony of the Life Ball in front of City Hall in Vienna, Austria, Saturday, May 16, 2015. The Life Ball is a charity gala to raise money for people living with HIV and AIDS. (AP Photo/HerwigPrammer)

Costumed guests pose for photographers during the opening ceremony of the Life Ball in front of City Hall in Vienna, Austria, Saturday, May 16, 2015. The Life Ball is a charity gala to raise money for people living with HIV and AIDS. (AP Photo/Herwig Prammer)

Actors perform on stage during the opening ceremony of the 23rd Life Ball in Vienna, Austria May 16, 2015. Life Ball is Europe's largest annual AIDS charity event and takes place in Vienna's city hall. REUTERS/Leonhard Foeger

Francesca von Habsburg performs on stage during the opening ceremony of the 23rd Life Ball in Vienna, Austria May 16, 2015. Life Ball is Europe's largest annual AIDS charity event and takes place in Vienna's city hall. REUTERS/Leonhard Foeger

Tens of thousands of spectators pushed against barriers to ogle paying guests in formal dress rubbing shoulders with celebrities, party-goers dressed in little more than body paint and cross-dressers in wild costumesPicture: AP Photo/Herwig Prammer

Brigitte Nielsen (R) and Alice Tumler perform in a flamboyant display with models and dancers in hair-raising wigs and outfits

(Picture: Jürgen Hammerschmid, Inge Prader)

Actor Andreas Vitasek performs on stage during the opening ceremony of the 23rd Life Ball in Vienna, Austria May 16, 2015. Life Ball is Europe's largest annual AIDS charity event and takes place in Vienna's city hall. REUTERS/Leonhard Foeger

Burlesque artist Dita Von Teese...Picture: AP Photo/Herwig Prammer

(AP Photo/Herwig Prammer)

U.S. actor Sean Penn makes a speech during the opening ceremony of the Life Ball in front of City Hall in Vienna, Austria, Saturday, May 16, 2015.

Models perform on stage during the opening ceremony of the Life Ball in front of City Hall in Vienna, Austria, Saturday, May 16, 2015. The Life Ball is a charity gala to raise money for people living with HIV and AIDS. (AP Photo/Herwig Prammer)

South Africa-born actress Charlize Theron makes a speech during the opening ceremony of the Life Ball in front of City Hall in Vienna, Austria, Saturday, May 16, 2015. The Life Ball is a charity gala to raise money for people living with HIV and AIDS. (AP Photo/Herwig Prammer)

Mary J. BligePicture: AP Photo/Herwig Prammer

An artist poses for a photo at the opening ceremony of the 23rd Life Ball in Vienna on May 16, 2015 (AFP Photo/Christian Bruna)

Life Ball – Europe's most spectacular party. (Picture: Jürgen Hammerschmid, Inge Prader)

Kelly Osbourne at the 23rd Life Ball in Vienna on May 16, 2015. Image Credit: AFP

Austrian singer and European Song Contest winner 2014 Conchita Wurst

Guests arrive for the opening ceremony of the 23rd Life Ball in Vienna May 16, 2015. Life Ball is Europe's largest annual AIDS charity event and takes place in Vienna's city hall. REUTERS/Leonhard Foeger

Actress Roseanne Barr arrives for the opening ceremony of the 23rd Life Ball in Vienna, Austria May 16, 2015. Life Ball is Europe's largest annual AIDS charity event and takes place in Vienna's city hall. REUTERS/Leonhard Foeger

Charlize Theron and partner Sean Penn attend the Life Ball in Vienna, Austria on Saturday

A model performs on stage while wearing fashion designed by Jean Paul Gaultier during the opening ceremony of the 23rd Life Ball in Vienna, Austria May 16, 2015. Life Ball is Europe's largest annual AIDS charity event and takes place in Vienna's city hall. REUTERS/Leonhard Foeger

A costumed guest poses for photographers during the opening ceremony of the Life Ball in front of City Hall in Vienna, Austria, Saturday, May 16, 2015. The Life Ball is a charity gala to raise money for people living with HIV and AIDS. (AP Photo/Herwig Prammer)

British singer Sophie Ellis-Bextorperforms on stage during the opening ceremony of the Life Ball in front of City Hall in Vienna, Austria, Saturday, May 16, 2015. The Life Ball is a charity gala to raise money for people living with HIV and AIDS. (AP Photo/HerwigPrammer)

Carmen Electra

(AP Photo/Herwig Prammer)

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