ONLY mad dogs and Englishmen go out in the midday sun – and Englishwomen on bicycles in Portugal’s beguiling Alentejo region.

Anyone who has not seriously cycled for years might approach an activity holiday with some apprehension. Will the legs handle 30 miles a day, in temperatures approaching 30 degrees? Will the nerves stand up to whizzing down coastal paths and pedalling past farmland – hence those maddening dogs?

The answer is a resounding yes, thanks to a top-of-the-range 21-gear bike with ultra-comfortable gel saddle. Also, helping us along the way were the frequent coffee and water stops in welcoming cafes, picnic lunches in shady forest glades and that tantalising promise of a wonderful evening meal and local wines in a comfortable boutique hotel beside a swimming pool, a lake or the sea.

The Alentejo, on Portugal’s south-western coast between Lisbon and the Algarve, is largely unknown to the tourists who have flocked to the neighbouring Algarve for years. It’s a region ripe for discovery, for its stunning scenery, fine food, friendliness and outstanding value.

Unspoilt by high-rise developments or industry, it boasts the largest coastal natural park in Europe.

Cycling along country trails, through cork plantations, skirting deserted beaches and passing charming little fishing villages is the green way to go.

We set our own pace, stopping for swims or sightseeing, shopping for crafts, exploring smugglers’ caves or dozing in the dunes as mood and energy levels dictated.

Armed with an intimidating-looking Carta Militar de Portugal – a military map of Portugal – it was almost impossible to get lost and we were fine – until we took directions from a wizened shepherd sitting in the doorway of his caravan.

The key to a relaxed cycling experience is good preparation. We got an excellent briefing from Headwater’s specialist rep, Ricardo; detailed and accurate route maps and directions; trainers rather than sandals; a hat to avoid sunstroke and plenty of food and water.

Our luggage was transported each day to our next destination so we carried only what we needed for the ride.

We could afford to be leisurely, sampling the cured meats, succulent olives and irresistible pastries at pit stops. This is no Tour de France sprint – although there was efficient back-up for emergencies and breakdowns.

When I hit a problem with the chain and gears my cycling buddy was clued-up enough to make running repairs. Next day the ailing bike was changed for another.

Our first base was the Hotel Verdemar in Casas Novas – run by chef Nuno and his Dutch wife Christine. Their rural retreat is packed with his colourful artwork, and you swing lazily in a hammock slung between fruit trees, coo at newborn lambs and generally relax.

Dinners were divine – quail, hake with seafood and roasted vegetables and orange cake. Breakfasts were also plentiful. With so many calories to work off we opted for the longer of the two possible routes.

Following a route map makes you more aware of the scenery around you. Instead of conventional signposts you spot turnings by landmarks such as a ruined windmill, the lightning-struck stump of a cork tree or the street lined with cannon balls. Other pointers included the farmhouse with horses’ heads on the gateposts – all markers reduced to a blur when you drive.

Liberated from your air-conditioned bubble you breathe in the scents of pine, eucalyptus, lavender and hundreds of colourful plants that thrive in a climate boasting 300 days of sunshine a year.

Descriptions of terrain take on a new significance: easy, flat, cruising, undulating, gradual and shallow are music to the ears.

Conversely, testing climb, sandy surface and rough track pose more of a challenge. Also, “150m – so steep we recommend you walk – then push your bike up before remounting”, means precisely that.

Usually, climbs are worth the effort for spectacular views. My favourite was on a track hugging the coast where, cooled by breezes from the crashing Atlantic, we marvelled at the unique sight of white storks wheeling above roosts balanced on the pinnacles of rocks.

We stood transfixed, poised on cliffs sculpted by millions of years of erosion from waves and wind.

Wending our way inland, our next stop was Vila Nova de Milfontes. We stayed at the Hotel Tres Marias – named after Swiss chef and owner Balthasar’s donkey, pig and goat. It was a stylishly-modern farmhouse conversion set against a backdrop of purple mountains.

Our adventure the next day took in more coastal routes.. We succumbed to the temptation of boiled shrimp and octopus salad at A Barca Tranquitanas – a pretty restaurant overlooking a small harbour.

A mushroom-shaped water tower loomed in the distance as we cycled beside pine trees, a fragrant eucalyptus grove and emerald-green grass being cultivated for golf courses and football grounds.

The tower marked our final destination: Brejao's Cerro da Fontinha – a complex of 150-year-old farmhouse and cottages lovingly restored by Miguel from local stone and wood. It had a charm all of its own.

Although Headwater promises a life changing holiday experience, I found it a thigh-changing experience too. With muscles as hard as well-pumped tyres, I vow to keep them honed by ditching the bus for a bike– or by joining gym sessions when English weather can't match that of the fair Alentejo.

TRAVEL FACTS Gill Martin was a guest of Headwater Holidays (headwater.com) which offers a seven-night Contrasts of Portugal Cycling independent hotel-to-hotel holidays from £1,059, including continental breakfasts, three picnic lunches, five evening meals, bicycle hire, route notes/local maps, and luggage transportation.

With flights into Faro from Heathrow, prices start at £1,264.

Useful websites: Beiras (Centro de Turismo Region) visitcentro.com; Alentejo at visitalentejo.com; Portugal at visitportugal.com.