This November, Will and I are swapping the comforts of home for the Moroccan Sahara — trekking just over 100km on foot in five consecutive days, to raise money for the St. James's Place Charitable Foundation.

We'll start in the foothills of Jebel Bani, south of Zagora, climb the trek's one and only mountain pass on day one, and then it's desert all the way: dry riverbeds, stony plateaus and the great dunes of Erg Chegaga, finishing at the oasis town of M'Hamid — the last village before the open Sahara. Four nights wild camping under some of the darkest, most star-filled skies on Earth, with camels carrying the kit and pre-dawn starts to beat the heat. Robin is very excited for the stars and camping.

We've (aka Will) plotted the route from the GPS tracks, so we know exactly what's coming:

- Day 1: 16km over the Jebel Bani pass (1,067m)

- Day 2: the monster: 34km (21 miles) in one day, nine to ten hours on our feet, ending in the dunes

- Day 3: 23km of dunes and hard rocky plateau

- Day 4: 20km across the stony desert plain, with 93km in our legs by nightfall

- Day 5: a final 9km through the dunes into M'Hamid

It promises to be an unforgettable experience, but also a serious challenge. The distance of two and a half marathons back-to-back-to-back, on sand and rock, in desert heat. We're deep into training already and will have put in hundreds of miles before we fly.

Most importantly, we're doing it to raise as much as we possibly can for the St. James's Place Charitable Foundation.

The Foundation supports small and medium sized charities across the UK and overseas, particularly those working with children who are disadvantaged physically, socially or economically. It also supports hospices, mental health charities and organisations providing cancer support.

And there's an added reason to give generously: St. James's Place Wealth Management will match every penny we raise. Every donation has twice the impact — £10 becomes £20, £25 becomes £50 and £50 becomes £100.

There will be sore feet, long days and (at least one) very early alarm, but knowing what we're raising money for will make every kilometre count.

However big or small, we'd be enormously grateful for your support. Thank you!