Question: Tamberg's Concerto Grosso, Op. 5 was awarded a gold medal at the 6th World Festival of Youth and Students, which was held in what city?
Context: The 15th World Festival of Youth and Students (WFYS) was organized by the World Federation of Democratic Youth (WFDY) in Algiers, Algeria, from 8 to 16 August 2001 for nine days, under the slogan "Let's globalize the struggle for Peace, Solidarity, Development, against Imperialism".  The festival was the first organized in an Arab country, as well as the first in Africa and brought together 11,000 delegates from over 100 countries from around the world.  International preparatory meetings took place in Cuba, India, Cyprus and Algeria itself.  The event came after the successful revival of the festival movement at the 14th World Festival of Youth and Students in Havana, Cuba, and marked a continuation of the internationalist and anti-imperialist youth festival spirit. George Balanchine to Antonio Vivaldi's "Concerto Grosso in B minor" and the first movement of his "Concerto Grosso in E major", Op. 3, nos. 10 and 12, respectively; in 1976 he added Arcangelo Corelli's "Sarabanda, Badinerie e Giga", second and third movements.  The premiere took place on November 21, 1957, at City Center of Music and Drama, New York, with lighting by Mark Stanley.  The original version placed the musicians on stage with a square dance caller calling the steps; from its 1976 revival the caller was eliminated, the orchestra placed in the pit, and a solo added for the "premier danseur" to the Corelli "Sarabanda".  The Pacific Northwest Ballet restored the caller for one performance at the 2007 Vail International Dance Festival. The Concerti Grossi, Op. 6, or Twelve Grand Concertos, HWV 319–330, are 12 concerti grossi by George Frideric Handel for a concertino trio of two violins and violoncello and a ripieno four-part string orchestra with harpsichord continuo.  First published by subscription in London by John Walsh in 1739, in the second edition of 1741 they became Handel's Opus 6.  Taking the older concerto da chiesa and concerto da camera of Arcangelo Corelli as models, rather than the later three-movement Venetian concerto of Antonio Vivaldi favoured by Johann Sebastian Bach, they were written to be played during performances of Handel's oratorios and odes.  Despite the conventional model, Handel incorporated in the movements the full range of his compositional styles, including trio sonatas, operatic arias, French overtures, Italian sinfonias, airs, fugues, themes and variations and a variety of dances.  The concertos were largely composed of new material: they are amongst the finest examples in the genre of baroque concerto grosso. He was trained under Grigory Ginsburg at the Moscow Conservatory.  Dorensky was awarded a Gold Medal at the 5th World Festival of Youth and Students and the 1957 Rio de Janeiro Competition's 2nd Prize, which allowed him to perform throughout Western Europe and America. Concerto grosso in G minor, Op. 6, No. 8 by Arcangelo Corelli, known commonly as the Christmas Concerto, was commissioned by Cardinal Pietro Ottoboni and published posthumously in 1714 as part of Corelli's "Twelve concerti grossi, Op. 6".  The concerto bears the inscription "Fatto per la notte di Natale " (made for the night of Christmas).  Its composition date is uncertain, but there is a record of Corelli having performed a Christmas concerto in 1690 for the enjoyment of his new patron. Eino Tamberg's Concerto Grosso, Op. 5, was composed in 1956.  It was awarded a gold medal at the 6th World Festival of Youth and Students the following year and was subsequently performed through both the Eastern and Western Blocs, launching the Estonian composer's career. Zahra Kiani (born September 26, 1999) is an Iranian Wushu (Taolu) athlete.  Kiani is the 6th world junior Wushu championships Changquan and Qiangshu gold medalist.  She also won the silver medal for Jianshu with the score of 9.39 behind the Chinese athlete Mengxuan ZHENG who won the gold medal with the score of 9.40.  Kiani was the most medal winning athlete of the 6th world junior Wushu championships and was called "The Phenomenal".  She is the first Iranian female athlete who accomplished grabbing a medal in a world Wushu championship with winning the silver medal with the score of 9.52 following the Russian athlete Sandra Konstentinova with the score of 9.53. The 6th World Festival of Youth and Students (Russian: Всемирный фестиваль молодёжи и студентов) was opened on 28 July 1957, in Moscow, Soviet Union.  The festival attracted 34,000 people from 130 countries.  This became possible after the bold political changes initiated by Nikita Khrushchev.  It was the first World Festival of Youth and Students held in the Soviet Union, which was opening its doors for the first time to the world. Nani Bregvadze (Ge.  ნანი ბრეგვაძე, Rus.  Нани Брегвадзе, born 21 July 1936 in Tbilisi) is a Georgian Soviet and Russian singer.  She was born, raised and started her career in Soviet Georgia in the USSR, then gained USSR-wide popularity during 1957 6th World Festival of Youth and Students.  Bregvadze has performed both with the Georgian music groups and solo. Lim Su-kyung (also spelled as Lim Soo-kyung; Hangul: 임수경, 림수경 ; Hanja: 林秀卿 ; born 6 November 1968) is a South Korean activist and politician.  She is best known for attending the 13th World Festival of Youth and Students, held in North Korea and praising North Korean leader Kim Il Sung in 1989, without first obtaining permission from the South Korean government. <ref name="Kyunghyang09/09"> </ref> She attended the festival representing the student organization "Jeondaehyop", now known as Hanchongryun.  Upon her return to South Korea, she was arrested and sentenced to 5 years' imprisonment.
Answer: Moscow, Soviet Union