‘THE Ness of Brodgar is the UK’s largest assembly of Neolithic art and evidence that Orkney’s population 5000 years ago may have been as large as today. It’s also a place of global interest,” says Nick Card, the site’s senior projects director, as we peer across the Heart of Neolithic Orkney, a UNESCO World Heritage Site since 1999.

It’s a landscape about to open up for six weeks, allowing a unique insight into the world of our ancestors on an island that bewitches down the ages.

The Ness of Brodgar is just one part of the Unesco-protected sweep of history that cuts a swathe through the heart of Orkney’s mainland. In archaeological dig terms it’s a newcomer, only under excavation since 2004. From next Wednesday (until August 17), free guided tours are opening up this massive complex of monumental sites dating back more than 5000 years for the first time since Covid hit. It’s no museum piece, as you’ll see archaeologists working away, unearthing further Neolithic and even older Mesolithic treasures.

Orkney is alive with prehistory. The BBC recently hailed it as the “Ancient Capital of Britain”. Card thinks that may be a touch dramatic, but does estimate the Neolithic population could have been anything up to 20,000, similar to today. In my head, this turns the London-centric map of Britain upside down.

I move to the southern fringes of the Unesco area, the Stones of Stenness, learning how all the sites fit together. To the north-east, the tomb of Maeshowe lines up, and west across the Ness of Brodgar lies its famous henge, the Ring of Brodgar. Beyond that is the finest Neolithic village I’ve ever seen, at Skara Brae. It’s all set in a spectacular natural amphitheatre betwixt the freshwater of Loch Harray and the brackish Loch Stenness. A line of low hills brood behind, with the hulk of Hoy haunting the distance.

The National: The stones of StennessThe stones of Stenness

The Stones of Stenness used to form a circle as part of the UK’s oldest henge but only four of the original circle stones still vault up to 5m high. One was destroyed a farmer, incensing the Orcadians so much they tried to burn his house down. Twice.

It’s a humbling experience standing underneath the stones, gazing skywards up a stone sentinel that has stood here since before the Pyramids. I explore the Neolithic village of Barnhouse too, which lies in the shadow of the Stenness.

Following the line north from Stenness to Maeshowe, I’m guided by the Barnhouse Stone. I’m in good company as the sun is guided too during the winter solstice, when it strikes light down the narrow entrance to this 5000-year-old tomb. Knowledgeable tour guide Robert Vasey leads the way into what he tells me is simply the “finest Neolithic building in north-west Europe”.

I’m gutted when Vasey tells me vandals have been in recently and carved graffiti into the darkened chamber we stand in. He smiles and says: “We’ve learned to forgive the Vikings who broke in during the 12th century as they left a collection of 33 runic inscriptions.”

He adds: “There are only 60 in total across the UK. Some speak of hidden treasure, some are poetic; others I’d better not repeat to you.”

Cutting west across the ancient isthmus of Brodgar I come to the famous henge. Elaine Clark, an onsite ranger, shares its importance: “It may be the ‘baby of the family’ at around 4500 years old but it’s part of the Heart of Neolithic Orkney story that runs from cradle to grave. It speaks of a community pooling resources rather than fighting against each other.”

Walking around the 27 stones it’s easy to see what a beacon it was in Neolithic times, set at the heart of an arduously dug three-metre-deep ditch. It was a spectacular stage. For what we don’t yet know.

Orkney itself is a stage and not just for Neolithic history. I savour an in-depth tour of the legendary Highland Park whisky distillery with five fine drams, walk on a trio of white sand beaches and ramble around the mysterious Broch of Gurness, which also sports Iron Age and Pictish houses.

A life-affirming highlight is the Italian Chapel, a pair of old Nissen huts quite brilliantly fashioned into an elegant place of worship, using scrap forged by prisoners of war during the Second World War.

And there is always more Neolithic history – I’ve not even taken you round the most famous site of Skara Brae, nor the glorious chambered tomb at Unstan – head here if you cannot get a ticket to Maeshowe.

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My trip ends in the restaurant at the grandly historic Kirkwall Hotel, where I’m staying with a room peering out over the busy harbour.

Over plump local scallops and Orkney lobster, I meet Leslie Tait (www.orkneytourguide.com) who talks of the miracle of Maeshowe: “I just don’t know how they did it, today it would be a tough job with machinery – it’s a Neolithic miracle.”

Orkney is a Neolithic miracle too, one you’ve got a unique chance to delve even deeper than you normally can for six weeks this summer.

lNorthlink (www.northlinkferries.co.uk) ferries sail to Orkney. More information www.visitscotland.com lThe Ness of Brodgar excavations are funded by donations – for more information see www.nessofbrodgar.co.uk lThe rest of the Neolithic sites in this article are currently open, though booking ahead is essential at Maeshowe