The sponsored trek makes for a great holiday. And, says Lee Levitt, it has become an important part of some charities' finances

I've partied in Cuba, thrown up as altitude sickness kicked in on Kilimanjaro in Tanzania, cycled through villages carved into the rock in Morocco's Atlas Mountains, and been pursued for a mile by a souvenir seller along the Great Wall of China - and all in the name of charidee.

I've partied in Cuba, thrown up as altitude sickness kicked in on Kilimanjaro in Tanzania, cycled through villages carved into the rock in Morocco's Atlas Mountains, and been pursued for a mile by a souvenir seller along the Great Wall of China - and all in the name of charidee.

The charity holiday market - which now stretches to horse-riding in Mongolia and rafting through the Mexican jungle - is an innovative and resourceful response to the growing demand for adventure holidays, underpinned, of course, by the need of charities to face up to an increasingly competitive funding environment.

In terms of marketing, its achievement in having jazzed up and increased audience awareness of an often tired and overlooked product has been inspired. Indeed, Simon Albert, the co-founder of the north London-based Charity Challenge, which operates more than 100 "challenges" each year, trained as a brand manager at Nestlé UK where he marketed Nescafé coffee before identifying a niche in the expedition market five years after his first charity trek in Jordan. Charity Challenge has helped raise around £15m from more than 550 challenges since 1999.

Provided you can overcome the pang of awkwardness associated with the fact that others are, often very generously, subsidising your holiday (all in a noble cause, mind), the experience is an overwhelmingly positive one. From the training to the fund-raising to the trip itself, it is a test of one's resources, organisational abilities, communication skills, and, not least, contacts.

One of the great features is the camaraderie that often develops, as I found while climbing Kilimanjaro for the One to One charity in aid of needy immigrants in Israel. At 18,000 feet, inner reserves and determination tend to go only so far when your head is pounding away and your muscles are giving out. Knowing that I couldn't have done it without the help of others was one of those fabled seminal moments that the tightly knit nature of the charity holiday group experience is, in some ways, primed to produce.

Often because of the nature of the "challenge", as many of the holidays are called, there's a certain amount of toughing it involved - on Kilimanjaro we camped out for a week - with a smart hotel serving as an end-of-trip reward. Early rises and going to the loo in the open also featured. But all of this, along with al fresco meals cooked by our travelling catering team, helped to bond the group and was, in many ways, part of the attraction.

Paying for the trip involves a registration fee which, according to a rough guide from Classic Tours - the self-styled "originators of worldwide challenges in aid of charity" - can be under £100 for a one- to four-day event, requiring less than £1,000 of sponsorship, rising to £200 to £300 for a 7- to 10-day holiday for which £2,000 to £2,500 of sponsorship is needed. Some charities ask for up to £500 as a down payment.

With the registration fee generally accounting for 20 to 35 per cent of the trip's cost, the balance - often in the region of £1,000 - is made up by the fund-raising. Over and above this, the money goes to the charity. It's a win-win situation - the charity gains; the company organising it for them (where there is one) gains; and you, the fund-raising holiday-goer, gain, too.

The fund-raising can start up to six months before the trip and sometimes continues after it, along with copious letter-writing, or e-mails, to donors. It requires a lot of organisation and planning, no small amount of persistence, ingenuity and (ideally) commitment to the cause.

Before the Cuba trek with One to One, I held a £10-a-head party in a wine bar with another trekker. However, much of the sponsorship came from work contacts, with Travelex providing corporate sponsorship in the form of sweatshirts.

But is there not something faintly immoral about the fact that much of the money ostensibly raised for the charity is actually funding the cost of the trip? Whereas in the early days, when this aspect was largely glossed over, the answer may have been "yes", many companies organising charity holidays are now at pains to point out the costs, leaving it up to the fund-raiser to point them out, if they wish, to prospective donors.

For some charities, their holidays programme forms an indispensable part of their annual fund-raising target. Norwood, for whom I cycled in Morocco, has raised £12.4m through its rides since they began in 1992, contributing more than 10 per cent of the child and family services charity's fund-raising target in that time.

Gordon Fox, 68, of Surrey, who initiated them in a joint ride with the Edinburgh Medical Missionary Society in Israel, and who has been on more than 20 trips, said: "We wouldn't have been able to survive without them. In addition, it's made people more aware of the charity, so we have received support indirectly as well as directly."

Some charities incorporate an aspect of their work into the trip, if possible directly through a visit to their chosen project. Before a trek through the Cederberg Mountains in South Africa with the One to One Children's Fund, in aid of children infected with, and affected by, the HIV/Aids virus, we visited the Aids research ward at the Groote Schuur Hospital in Cape Town to meet some of those we were supporting; and at the end, we went to a township kindergarten which the charity was also helping. While on the Morocco ride, four people with learning disabilities who live in Norwood's Ravenswood Village in Berkshire or in one of the charity's homes went on tandems with able-bodied riders, providing a great example of inclusivism at work (albeit on holiday). Linking the trip to the charity's work helped bring the fund-raising aspect into cold focus and cemented its identity as a charity holiday.

In terms of the good they do, the sense of fulfilment they bring and the knock-on effects for the charities concerned, the holidays have proved an admirable invention. And if some may cavil at the euphemistic terms used to dress up a perceived holiday in the language of an endeavour, it is a small price to pay on the adventurous road down which they have enabled charities to travel.