London ( CNN ) -- Queen Elizabeth II is marking her 86th birthday Saturday privately at Windsor Castle , a palace spokesman said . The Queen also has an official birthday in June , which will be celebrated publicly as part of events to mark the Diamond Jubilee . The Royal Gibraltar Regiment fired a 62-gun salute for her real birthday at the Tower of London , Retired Lt. Col. Stuart Green said . Hundreds of guests gathered for the salute , which included 21 guns for the Queen 's birthday , 21 because it 's a royal palace and 20 guns to show the City of London 's loyalty to the monarch , Green said . The regiment , usually based in Gibraltar , is currently in London for ceremonial duties including guarding Buckingham Palace and the Tower of London , he said . A 41-gun salute in Hyde Park and a 21-gun salute in Windsor Great Park were also held to honor the Queen . The salute in Hyde Park was performed by the King 's Troop Royal Horse Artillery , using teams of galloping horses to pull six World War I-era guns into position . The 41 rounds were then fired at 10-second intervals , the Ministry of Defence said . On her official birthday each June , the Queen and other members of the royal family attend the Trooping the Colour military parade in central London . CNN 's Bharati Naik and Laura Smith-Spark contributed to this report .
NEW : Teams of horses pull guns into position in Hyde Park for a 41-gun salute . A 62-gun salute is fired at the Tower of London for the Queen 's 86th birthday . The Queen has an official birthday in June when she takes part in public events . She celebrates her Diamond Jubilee -- marking 60 years on the throne -- this year .