The Mariinsky Theatre (Russian: Мариинский театр, tr. Mariinskiy teatr, also transcribed as Maryinsky or Mariyinsky) is a historic theatre of opera and ballet in Saint Petersburg, Russia. Opened in 1860, it became the preeminent music theatre of late 19th-century Russia, where many of the stage masterpieces of Tchaikovsky, Mussorgsky, and Rimsky-Korsakov received their premieres. Through most of the Soviet era, it was known as the Kirov Theatre. Today, the Mariinsky Theatre is home to the Mariinsky Ballet, Mariinsky Opera and Mariinsky Orchestra. Since Yuri Temirkanov's retirement in 1988, the conductor Valery Gergiev has served as the theatre's general director. Under Yuri Temirkanov, Principal Conductor from 1976 to 1988, the Opera Company continued to stage innovative productions of both modern and classic Russian operas. Although functioning separately from the Theatre’s Ballet Company, since 1988 both companies have been under the artistic leadership of Valery Gergiev as Artistic Director of the entire Theatre. The Opera Company has entered a new era of artistic excellence and creativity. Since 1993, Gergiev’s impact on opera there has been enormous. Firstly, he reorganized the company’s operations and established links with many of the world's great opera houses, including the Royal Opera House, Covent Garden, the Metropolitan Opera, the Opéra Bastille, La Scala, La Fenice, the Israeli Opera, the Washington National Opera and the San Francisco Opera. Today, the Opera Company regularly tours to most of these cities. Gergiev has also been innovative as far as Russian opera is concerned: in 1989, there was an all-Mussorgsky festival featuring the composer’s entire operatic output. Similarly, many of Prokofiev’s operas were presented from the late 1990s. Operas by non-Russian composers began to be performed in their original languages, which helped the Opera Company to incorporate world trends. The annual international "Stars of the White Nights Festival" in Saint Petersburg, started by Gergiev in 1993, has also put the Mariinsky on the world’s cultural map. That year, as a salute to the imperial origins of the Mariinsky, Verdi's La forza del destino, which received its premiere in Saint Petersburg in 1862, was produced with its original sets, costumes and scenery. Since then, it has become a characteristic of the "White Nights Festival" to present the premieres from the company’s upcoming season during this magical period, when the hours of darkness practically disappear as the summer solstice approaches. Presently, the Company lists on its roster 22 sopranos (of whom Anna Netrebko may be the best known); 13 mezzo-sopranos (with Olga Borodina familiar to US and European audiences); 23 tenors; eight baritones; and 14 basses. With Gergiev in charge overall, there is a Head of Stage Administration, a Stage Director, Stage Managers and Assistants, along with 14 accompanists.