Elisabeth von Magnus (née Countess Elisabeth Juliana de la Fontaine und d'Harnoncourt-Unverzagt; born 29 May 1954 in Vienna) is an Austrian classical mezzo-soprano.
 The daughter of conductor Nikolaus Harnoncourt and violinist Alice Harnoncourt, her professional name comes from her first marriage to Ernst-Jürgen von Magnus.
 She studied recorder in Vienna, theater at the Mozarteum in Salzburg and voice with Hertha Töpper at the Conservatory of Munich.
 Her other teachers have included Paul Schilhawsky.
 Early in her career, she performed as a recorder soloist with the Concentus Musicus Wien.
 She has also worked for ORF as a presenter and announcer.
Iris Vermillion (born 1960) is a German operatic mezzo-soprano.
 A member of the Deutsche Oper Berlin from 1988, she has enjoyed an international career, appearing in Amsterdam with Nikolaus Harnoncourt and at the Salzburg Festival, among others.
The Vienna New Year's Concert (Neujahrskonzert der Wiener Philharmoniker ) is a concert of classical music performed by the Vienna Philharmonic that takes place each year in the morning of New Year's Day in Vienna, Austria and is regarded by many as the most important classical concert worldwide.
 It is broadcast live around the world to an estimated audience of more than 50 million in 73 countries in 2012 and 93 countries in 2017.
David Reichenberg (13 July 1950 - 10 June 1987) was an American oboist and a highly respected specialist on the baroque oboe.
 He was born in Cedar Falls, Iowa and learnt the flute, violin and piano as a child.
 He began his oboe studies with Dr Myron E. Russell of the University of Northern Iowa.
 Beginning in 1969, Reichenberg studied at the Indiana University School of Music, continuing his oboe studies with Jerry Sirucek, former oboist with the Chicago Symphony Orchestra.
 Graduating in 1972, Reichenberg moved to Salzburg, where he attended the Mozarteum.
 It was in Salzburg that Reichenberg met Nikolaus Harnoncourt, director of Concentus Musicus Wien.
 Reichenberg became increasingly interested in playing the oboe's repertoire on the instrument for which it had been written and, with the assistance of Harnoncourt, moved to Vienna in order to study baroque oboe with Jürg Schäftlein.
 He simultaneously studied oboe making with Paul Hailperin, building the instrument upon which he played for four years.
 Reichenberg took part in many concerts and recordings with Concentus Musicus, and gradually increased his activities with that group.
Kurt Equiluz (born 13 June 1929 in Vienna) is an Austrian classical tenor in opera and concert, known for recording works of Johann Sebastian Bach with Nikolaus Harnoncourt and Helmuth Rilling, a member of the Vienna State Opera as a tenor buffo from 1957 until 1983.
Rotraud Hansmann (born 1 March 1940) is an Austrian soprano in opera and concert.
 She was a singer in the recordings by Nikolaus Harnoncourt which began historically informed performances, such as Monteverdi's operas and works by Johann Sebastian Bach.
 She was a teacher at the University of Music and Performing Arts, Vienna.
Nikolaus Harnoncourt (Johann Nikolaus Graf [Count] de la Fontaine und d’Harnoncourt-Unverzagt; 6 December 1929 – 5 March 2016) was an Austrian conductor, particularly known for his historically informed performances of music from the Classical era and earlier.
 Starting out as a classical cellist, he founded his own period instrument ensemble, Concentus Musicus Wien, in the 1950s, and became a pioneer of the Early Music movement.
 Around 1970, Harnoncourt started to conduct opera and concert performances, soon leading renowned international symphony orchestras, and appearing at leading concert halls, operatic venues and festivals.
 His repertoire then widened to include composers of the 19th and 20th centuries.
 In 2001 and 2003, he conducted the Vienna New Year's Concert.
 Harnoncourt was also the author of several books, mostly on subjects of performance history and musical aesthetics.
The Lockenhaus Chamber Music Festival (alternate: "Internationales Kammermusikfest Lockenhaus"') is an annual chamber music festival located in the Austrian state of Burgenland.
 It is held at three venues in Lockenhaus: Burg Lockenhaus castle, Church of St. Nikolaus, and the old monastery of Lockenhaus.
 The New York Times has referred to as perhaps one of the "two most refined music festivals of all", and a European cultural treasure.
 While both older and younger talents perform, notable performers include Vladimir Ashkenazy, Nikolaus Harnoncourt, Heinz Holliger, Cho-Liang Lin, and András Schiff.
 According to its founder, violinist Gidon Kremer, the Lockenhaus Chamber Music Festival philosophically resembles the Marlboro Music Festival in Vermont, US.
Elisabeth Kulman (born 28 June 1973) is an Austrian classical singer who has performed operatic roles in soprano, mezzo-soprano and contralto repertory.
 She has appeared at opera houses in Vienna and internationally.
 She has performed early operas such as Legrenzi's "Il Giustino" as well as new works, creating the role of Gora in the premiere of Reimann's "Medea" at the Vienna State Opera.
 She recorded Lieder by Mussorgsky, Bach's "Christmas Oratorio" with Peter Schreier and Beethoven's "Missa solemnis" with Nikolaus Harnoncourt.
 From 2015, she has focused on concert singing.
Johann Sebastian Bach's music has been performed by musicians of his own time (including himself), and in the second half of the eighteenth century by his sons and students, and by the next generations of musicians and composers such as the young Beethoven.
 Felix Mendelssohn renewed the attention for Bach's music by his performances in the 19th century.
 In the 20th century Bach's music was performed and recorded by artists specializing in the music of the composer, such as Albert Schweitzer, Helmut Walcha and Karl Richter.
 With the advent of the historically informed performance practice Bach's music was prominently featured by artists such as Nikolaus Harnoncourt, Gustav Leonhardt and Sigiswald Kuijken.

Question: In what country did Nikolaus Harnoncourt conduct a concert in 2001 and 2003?
Answer: Austria