We had coffee and homebaked cakes in the lee of one stone while our other guide, Nick Thorpe, explained the layout and history. We also had a picnic at Durrington, got blasted by galeforce winds on the way up to Long Kennet and had an enjoyable walk down and across to Silbury Hill, the largest man made mound in Europe which has been literally tunnelled and shafted by the archaeologists - and still nobody really has a clue what it was built for.

But Sunday's dawn visit to Stonehenge was the highlight of Andante's Wessex archaeological weekend. Rather than simply drive to the site, park, walk around Stonehenge with 850,000 other people every year and drive away again, the sum of the weekend's parts so helped put the site into context.

And what was Stonehenge for? No idea, really. Clearly ceremonial, possibly ritual, almost certainly spiritual, as the huge turnouts for the solstices bear witness to. But having the bare bones of carbon-dated history explained and the interpretations so jauntily expounded by Andrew gave plenty of food for thought.

He is now a leading proponent in the project to close the A303 - which runs hard by Stonehenge - and revert the land back to grazing while building a two-kilometre tunnel for traffic. Even at 7am, the drone of traffic from the main road to the south-west was relentless. The prospect is fabulous but it was not surprising to hear that the government is dragging its heels - despite a government committee calling the current site a "national disgrace."

Still, it's not so bad when you've the place to yourself.

NEED TO KNOW

Andante Travels runs a number of Wessex Weekends - the next is August 10-12. The tour costs £295 per person, to include dinner with wine on Friday night, plus a guide and entrance fees to all sites. Phil Harding of Time Team will also give a private flint knapping workshop/demo. The company has also just launched a new series of archeological tours called Bare Bones, with many aimed at families.

The company will suggest accommodation options for you - in keeping with the exclusive access theme of the weekend, we stayed at Sarum College, a theological college in The Close, Salisbury. Many rooms at the college look out to Salisbury Cathedral - and the gates to the old city are locked at night, so you and the old town's residents have the cathedral to yourselves first thing in the morning. A night's B&B costs from £45 a single, £75 a double.

One of Andante's tour managers, Alex Casey, is part-owner of Marrakesh restaurant in Salisbury - I can recommend the leg of Wiltshire lamb stuffed with rice and mushrooms.

Stonehenge: For more information, go to the English Heritage site - where you can also download application forms for Stone Circle Access, which allow groups of up to 26 access for one hour. Summer Solstice is held at Stonehenge on June 20-21 when access is allowed on the shortest night. For more details: www.english-heritage.org.uk

MORE SECRET ACCESS

Pompeii: Andante Travels also arranges special access to some of the houses of Pompeii, and has a privileged arrangement to be shown around the conservation workshops of the excavations by the chief conservator. Other special site accesses have been in Anatolia, Turkey and Nicopolis, the Roman town. The company's archaeologist guides have friends and colleagues who excavate all over the world and there are many unscheduled visits to excavations in progress.

Machu Picchu, Peru: There is a hotel at the entrance run by Orient-Express Hotels. While staying at The Sanctuary Lodge doesn't allow exclusive access per se, the logistics mean you'll have Macchu Picchu virtually to yourself first thing in the morning bar the odd backpacker arriving down The Inca Trail. Visitors on the first train from Cuzco arrive at Macchu Piccu at 9.30am - you can get onto the site at 6am. But youll pay for it - rates start at a whopping £367 for a double room.

Great Wall of China: Kempinski Hotels operates a property near the Shuiguan section of the Great Wall, about one hour from Beijing. In September, 21 new villas were added to the original collection of villas, which are dispersed along the steep slope of a valley each with views of the Wall. A private path leads up to part of the unrestored or Wild Great Wall: the access is completely private.

St Mark's Cathedral, Venice: A one-hour visit outside normal opening times is part of a five-day art history tour to Venice from Martin Randall Travel to run from November 29. The tour also includes visits to private palaces.

Sistine Chapel, Rome: Martin Randall also runs a tour to Rome in November which includes private visits to the Chapel, Villa Medici and Galleria Borghese. Another company which can arrange private tours to the Chapel, Vatican and Villa Borghese is Special Tours, which also runs visits to private gardens and palaces in Sicily.

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