On May, 23 charity concert was given at the investigative detention center №1 “Kresty” within the framework of the XVIII International Musical Olympus Festival. Young musicians from St Petersburg and prize winners of prestigious music contests performed for the convicts. Unique double bass quartet “Quattrobass” opened the concert with the works by Russian composer А. Mirzoev. Then, to the quartet accompaniment, Elena Korzhenevskaya (soprano) sang “Ave Maria” by G. Caccini and Adele couplets from J. Schtrauss’ “Fledermouse”. The concert ended with the performance of button accordion player Dmitry Bezdenezhnykh, 1 prize winner of the International Accordion Prize “Città di Lanciano” in Italy, who performed pieces by V. Zubitsky, C. Dulfer, C. Velázquez Torres, and А. Piazzolla.