Queen Margrethe marks 40 years on Denmark's throne Queen Margarethe II of Denmark and Prince Henrik of Denmark make an appearance on the palace balcony to celebrate the queen's 40th jubilee. (CBS) The celebration of Queen Margrethe II of Denmark's 40th jubilee drew to a close Sunday evening with a gala dinner for European royalty at Christiansborg Castle in Copenhagen. Pictures: Queen Margrethe's 40th jubilee The weekend's events included a church service Sunday morning, a City Hall reception Saturday preceded by a horse-drawn carriage ride through the streets of the city and followed by a jubilee concert at the Royal Concert Hall. Tens of thousands of flag-waving Danes turned out Saturday to cheer the popular 71-year-old queen, known familiarly to them as "Daisy." She rode in an 1840 horse-drawn carriage, escorted by mounted Hussars, from Amalienborg Castle to a reception at City Hall. Among the royalty and heads of state attending the festivities were King Carl XVI Gustaf and Queen Silvia of Sweden, King Harald and Queen Sonja of Norway, the deposed monarch of Greece and family and Icelandic President Olafur Ragnar Grimsson. The queen, who can trace her lineage back to the Vikings, became queen on Jan. 14, 1972, after the death of her father, King Frederik IX.