Sophie, Countess Of Wessex and a team of riders begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland. The Countess of Wessex will cycle from, Edinburgh to Buckingham Palace, London in support of The Duke of Edinburgh's Award in its 60th year.

Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland. The Countess of Wessex will cycle from, Edinburgh to Buckingham Palace, London in support of The Duke of Edinburgh's Award in its 60th year.

Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

(C) Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland. 

(L-R) Sophie, Countess of Wessex and a team are waved off by Prince Philip, Duke of Edinburgh and Prince Edward, Earl of Wessex as they depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

Sophie, Countess of Wessex and a team of riders are waved off by Prince Edward, Earl of Wessex as they depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

(R-L) Prince Philip, Duke of Edinburgh and Prince Edward, Earl of Wessex during Diamond Challenge event on September 19, 2016 in Edinburgh, Scotland.

Prince Philip, Duke of Edinburgh during the Diamond Challenge event on September 19, 2016 in Edinburgh, Scotland. The Countess of Wessex will cycle from, Edinburgh to Buckingham Palace, London in support of The Duke of Edinburgh's Award in its 60th year.

Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

Britain's Sophie, Countess of Wessex, reacts boefore setting off on a bike from The Palace of Holyroodhouse, or Holyrood Palace, in Edinburgh, on September 19, 2016, enroute to Buckingham Palace in central London.

Britain's Sophie, Countess of Wessex, reacts before setting off on a bike from The Palace of Holyroodhouse, or Holyrood Palace, in Edinburgh, on September 19, 2016, enroute to Buckingham Palace in central London. The Countess is set to cycle from Edinburgh to London, a distance of 445 miles, in seven days, in support of the Duke of Edinburgh's Award (DofE), as part of her 'Diamond Challenge' - to mark the 60th anniversary of the DofE award.

Britain's Sophie, Countess of Wessex, reacts before setting off on a bike from The Palace of Holyroodhouse, or Holyrood Palace, in Edinburgh, on September 19, 2016, enroute to Buckingham Palace in central London.

Britain's Sophie, Countess of Wessex, depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland. 

Britain's Sophie, Countess of Wessex, smiles before setting off on a bike from The Palace of Holyroodhouse, or Holyrood Palace, in Edinburgh, on September 19, 2016, enroute to Buckingham Palace in central London.

Britain's Prince Philip, Duke of Edinburgh, waits to watch his daughter-in-law Britain's Sophie, Countess of Wessex set off on a bike from The Palace of Holyroodhouse, or Holyrood Palace, in Edinburgh, on September 19, 2016, enroute to Buckingham Palace in central London.

Britain's Prince Philip, Duke of Edinburgh, waits to watch his daughter-in-law Britain's Sophie, Countess of Wessex set off on a bike from The Palace of Holyroodhouse, or Holyrood Palace, in Edinburgh, on September 19, 2016, enroute to Buckingham Palace in central London.

Sophie, Countess of Wessex and a team of riders prepare to depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

Sophie, Countess of Wessex and a team of riders prepare to depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland. 

Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland

 Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland. 

Sophie, Countess of Wessex and a team are waved off by Prince Philip, Duke of Edinburgh as they depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

Sophie, Countess of Wessex and a team of riders are waved off by Prince Edward, Earl of Wessex as they depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

(L-R) Prince Philip, Duke of Edinburgh and Prince Edward, Earl of Wessex speak to wellwishers as Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

Sophie, Countess of Wessex is partaking in the ride in support of the Duke of Edinburgh's Award to celebrate the scheme's 60th anniversary

Sophie, Countess of Wessex is also the ship's sponsor of HMS Daring, which will be at sea during the ride.

(2-R) Sophie, Countess of Wessex is joined by six team members, including riders drawn from the four Royal regiments she is linked to - 5th Battalion The Rifles, RAF Wittering, Queen Alexandra's Royal Army Nursing Corps and Corps of Army Music

The Countess of Wessex chats to press at the Palace of Holyroodhouse in Edinburgh before the start of the cycle ride 



 Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.



Sophie, Countess of Wessex and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge on September 19, 2016 in Edinburgh, Scotland.

(R) Sophie, Countess of Wessex, and a team of riders depart the Palace of Holyroodhouse as they begin their Diamond Challenge

(2nd-L) Sophie, Countess of Wessex with Prince Philip, Duke of Edinburgh (3rd-L) and Prince Edward, Earl of Wessex (3rd-R) and other cyclists as she leaves the Palace of Holyroodhouse in Edinburgh at the start of a 450 mile cycle ride to Buckingham Palace in London

(2nd-L) The Duke of Edinburgh waves off the Countess of Wessex (3rd-L) while the Earl of Wessex looks on (left) as she leaves

Sophie, Countess of Wessex speaks with her father-in-law, Prince Philip, Duke of Edinburgh, before she leaves the Palace of Holyroodhouse in Edinburgh

Sophie, Countess of Wessex (center) crosses the border between Scotland and England at Carter Bar with other riders, as she takes part in a 450-mile cycling challenge from the Palace of Holyroodhouse in Edinburgh to Buckingham Palace in London

Sophie, Countess of Wessex (center) crosses the border and stops for a snap



Sophie, Countess of Wessex was in high spirits during a pit stop for her 'DofE Diamond Challenge', which marks the 60th anniversary of The Duke of Edinburgh's Award Scheme



Rachel McKenzie, a physical training instructor (PTI) at the Royal Military Academy Sandhurst, has been putting The Countess of Wessex (R) through her paces and is joining her on the trip, which will take about seven days to complete



The Countess of Wessex slipped into her lycra as she set off on a 450-mile palace-to-palace cycling challenge from Edinburgh to London on September 19, 2016



The Countess of Wessex left the Palace of Holyroodhouse in Edinburgh this morning before the start of a 450 mile cycle ride to Buckingham Palace in London



Sophie, Countess of Wessex and her team are pedaling from the Palace of Holyroodhouse to Buckingham Palace in support of the Duke of Edinburgh's Award to celebrate the scheme's 60th anniversary.



Sophie, Countess of Wessex left the Palace of Holyroodhouse in Edinburgh this morning before the start of a 450 mile cycle ride to Buckingham Palace in London

(L-R) Sophie, Countess of Wessex was waved off on the Diamond Challenge by Prince Philip, Duke of Edinburgh and her husband Prince Edward, the Earl of Wessex

(C) Sophie Countess of Wessex and other participants take a break during the DofE Diamond Challenge

Sophie, Countess of Wessex slipped into her lycra as she set off on a 450-mile palace-to-palace cycling challenge from Edinburgh to London on Monday. Here she is pictured stopping at Jedburgh Abbey

Prince Edward, Earl of Wessex kisses his wife Sophie, Countess of Wessex as she leaves the Palace of Holyroodhouse