John Caudwell is estimated to be worth �1.28bn

Staffordshire entrepreneur John Caudwell, 52, the founder of Phones 4 U, began the journey at the Parthenon on Sunday with six other riders.

The 2,300-mile trip across Europe will see them covering an average 100 miles-a-day before arriving in London at the end of the month.

All the money raised will go to the Caudwell Charitable Trust.

It will be used to help sick, disabled and terminally-ill children across the country.

Speaking before the start of the trek, Mr Caudwell said: "It's a massive challenge, with huge extremes of temperature and terrain to tackle.

"Many people's experience of cycling is no more than a few gentle miles around country lanes, or a ride to work. They might hit 16mph for a few yards down hill.

"But 16mph is a speed we will need to average all day for 18 days come hell, high water, crashes, mountains or punctures."

The cyclists, all businessmen from the Stoke-on-Trent and Stafford areas, have each raised �10,000 in sponsorship. The rest will come from other donations.

Their route takes in Naples, Rome, Milan, Geneva, Dijon and Paris.

Mr Caudwell, whose fortune was estimated at �1.28bn in the last Sunday Times Rich List, regularly cycles from his company's Stoke-on-Trent headquarters to business meetings in London.

He has previously completed three 1,000 mile-plus cycle rides, each raising more than �300,000.