LONDON -- Queen Elizabeth II marked her Diamond Jubilee on Monday with a message thanking all those who had supported her over her 60-year reign and reaffirming her dedication to serving the British people.

The 85-year-old monarch ascended the throne when her father, George VI, died on Feb. 6, 1952. She is the longest-serving monarch after Queen Victoria, who reigned for more than 63 years.

Before a year's worth of festivities to celebrate her milestone, the queen said she and her husband have been "deeply moved" to receive so many kind messages about her Diamond Jubilee.

"I am writing to thank you for the wonderful support and encouragement that you have given to me and Prince Phillip over these years," she wrote in a message to the nation. "In this special year, as I dedicate myself anew to your service, I hope that we will all be reminded of the power of togetherness and the convening strength of family, friendship and good neighborliness, examples of which I have been fortunate to see throughout my reign."

The queen's Diamond Jubilee will be feted with a series of regional, national and international events throughout 2012.

Over the course of 2012, members of the royal family – including Prince William and his wife, the Duchess of Cambridge – will fan out across the globe and travel to Commonwealth countries including Canada, Jamaica and Belize in honor of the queen's Diamond Jubilee.

The queen and Philip, also known as the Duke of Edinburgh, will stay closer to home, touring the U.K. from March to July.

The 2012 Diamond Jubilee weekend will be held from June 2-5, with the main highlight likely to be a huge pageant on the Thames river featuring a 1,000-strong flotilla.

Elizabeth expressed hope that the coming year will be a time to give thanks "for the great advances" since she took the throne and "look forward to the future with a clear head and warm heart."

Later Monday, the queen is slated to tour a nursery school and meet pupils there before watching a play about her 60 years as sovereign.

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  • Britain's Queen Elizabeth II leaves carrying flowers during a vist to Kings Lynn Town Hall in Kings Lynn, Norfolk on February 6, 2012 to start celebrations for her diamond jubliee 60 years to the day since she ascended to the throne. (BEN STANSALL/AFP/Getty Images)

  • Members of the King's Troop Royal Horse Artillery depart after firing a 41 gun salute in Hyde Park to mark the 60 anniversary of the accession of Her Majesty Queen Elizabeth II on February 6, 2012 in London, England. (Photo by Oli Scarff/Getty Images)

  • Soldiers from the King's Troop Royal Horse Artillery fire a 41 Gun Salute in Hyde Park, central London, on February 6, 2012, to mark the start of Diamond Jubilee celebrations for Britain's Queen Elizabeth II. CARL COURT/AFP/Getty Images)

  • Gunners from 105 Regiment Royal Artillery, fire a 21-Gun Royal Salute at Mills Mount Battery at Edinburgh Castle on February 6, 2012 in Edinburgh, Scotland. (Photo by Jeff J Mitchell/Getty Images)

  • Britain's Queen Elizabeth II leaves Kings Lynn Town Hall in Kings Lynn, Norfolk, on February 6, 2012 to start celebrations for her diamond jubliee 60 years to the day since she ascended to the throne. (BEN STANSALL/AFP/Getty Images)

  • Members of the King's Troop Royal Horse Artillery prepare to fire a 41 gun salute in Hyde Park to mark the 60 anniversary of the accession of Her Majesty Queen Elizabeth II on February 6, 2012 in London, England. (Photo by Oli Scarff/Getty Images)