Sofia Mayor Boyko Borisov forgot his usual leather jackets and jeans for a night of glamour and tuxedos in Austria.
Borissov and his girlfriend Tsvetelina Borislavova were guests at the Vienna Opera Ball, by the invitation of the city's mayor Michael Haupl.
Borislavova had chosen the same designer as the celebrity guest of the ball - Paris Hilton for her dress. Both appeared in models by Italian Roberto Cavalli.
Borissov spent the night in his Vienna counterpart's box because he isn't quite familiar with the traditional waltzes, as he himself admitted.