Cancer campaigner Jane Tomlinson's family will run two marathons in eight days - cycling 600 miles between them - to mark 10 years since she completed her first London marathon.
Mrs Tomlinson, who died in September 2007 aged 43, inspired thousands of people with her charity challenges while battling against terminal cancer.
She raised more that £1.85 million in seven years, despite her pain and illness, and the family have continued to raise funds for her charity, the Jane Tomlinson Appeal, since her death.
Now her husband Mike, 50, of Rothwell, West Yorkshire, and daughter Rebecca, 23, of Tooting, south London, are planning to run this year's Paris and London marathons, cycling the distance between them.
They will be joined by a team of cyclists as they take on a 100 mile-a-day route between the capitals.
After tackling the French run on April 15, they will cycle to Zeebrugge in Belgium. From there they will get the ferry to Hull and travel through the appeal's home turf of Yorkshire, before arriving in London ahead of its marathon on April 22.
Mr Tomlinson said: "I still struggle to comprehend the endurance feats Jane completed and the starting point was the 2002 London Marathon.
"The aim was to raise £5,000 and here we are 10 years and £4 million later.
"More than the money, Jane helped people change lives and to celebrate this we wanted to celebrate the anniversary in appropriate fashion."
Mrs Tomlinson was awarded the MBE for her work in June 2003 and later made a CBE.