A TROWBRIDGE schoolboy and his father are taking on a feat of endurance to raise money for an Alzheimer's charity - cycling 500km through the Sahara Desert.

Sebastian Bates and his father Peter, of High Street, Rode, are putting themselves through the challenge because Sebastian's grandmother Elizabeth Bates, died this year after suffering from the disease.

They wanted to do something impressive together so have planned the 500km cycle trek in Morocco.

Starting on October 27 at the north western edge of the Sahara Desert, they will ride over the High Atlas Mountains, reaching heights of more than 4,000m above-sea-level and then cruise down into Marrakech, one of the country's main Imperial cities.

The father and son will travel about 100km each day and will carry everything they need to sleep, eat, drink, and combat the snakes during the journey.

Seventeen-year-old Sebastian, a pupil at St Augustine's Catholic College in Wingfield Road, Trowbridge, said: "We wanted something hard, both physically and mentally, and we wanted to do it somewhere exciting.

"One of our friends was talking about the Sahara with its extreme climate and high mountains and we went for it.

"It's all in memory of my grandmother who died of Alzheimer's."

The sixth form student said: "The height gain will be the hardest thing over the first few days. That will be tough. We're carrying all our kit in the heat and dust. Of the six-day trek, five will be spent cycling and four days of that will be uphill.

"The last day will be fun I think because it's down hill. My strategy if it gets tough is never to stop. We won't have time to stop."

To donate to the cause visit www.justgiving.com/Bates_Family_Cycle_Trek and sponsor them.

Father-of-four Mr Bates, 48, is, in his words, an energetic but ageing Lieutenant Colonel in the Army whose military and civilian lives have taken their toll on his body.

He said: "There is no better way to bond with your teenage son over half term as well as avoiding all the other child minding duties."