On Monday, the Countess of Wessex sets off on an impressive 445 mile cycle from the Palace of Holyroodhouse in Edinburgh to Buckingham Palace to raise money for The Duke of Edinburgh's Award. Along with a team of five fellow cyclists from regiments with which she is associated, she will be waved off by her father-in-law The Duke of Edinburgh and her husband, The Earl of Wessex, before pedalling from Scotland to London in just seven days.
It's a challenge that Sophie, 51, has trained hard for since February, fitting in rides around out her work with the 80-plus organisations of which she is Patron.
The Countess of Wessexwill cycle an impressive 445 miles to Buckingham Palace
And in an interview with HELLO! at her Bagshot Park home a few days before her departure, she reveals which family members think she's mad, how her children feel about the challenge and recounts an amusing encounter with one passing driver.
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"I do think I'm ready," Sophie tells HELLO!'s royal correspondent Emily Nash. "It's been quite a long six months but I've put in the hours in the saddle, I've sweated the blood and tears, I'm physically and mentally ready to go now."
Read the full interview in next week's HELLO! out Monday.