Cairns and barrows are the most common kind of ancient site in West Penwith and across Britain.
Apart from neolithic longbarrows that come from an earlier time, the cairns and barrows were built in the bronze age from 2500 BCE onwards, peaking around 2200-1800 and tailing off around 1500. I have a feeling a few were built earlier in the 2000s, but there is no known physical evidence. Mounds have not been properly and comprehensively researched and dated.
Most barrows and cairns are solid, built of earth or earth and stones, sometimes with rocks.
Some are chambered cairns (there are lots of these on Scilly), and these are very different.
Mounds were built for a variety of purposes: to act as prominent landmarks, to mark places and territory and add features to the landscape, for geomantic purposes (energy-vortices and alignments), as shrines, for burial, as repositories (containing cists, urns or deposits), to act as viewing platforms (backsights), and even perhaps as stages for spectacles (some platform barrows) - and frequently they were multi-purpose.
A typical Penwith cairn - overgrown and befurzed but still there. This one is near the Nine Maidens stone circle, part of its complex. The orange creeper is a longtime indigenous parasite that seems to coexist happily with surrounding plants
Quite a few cairns have been damaged by antiquarians, treasure hunters and landowners, or by erosion. But many survive, dotted around, some in groups, with a few barrowfields (such as at Beacon Barrows).
Some barrows and cairns have energy-vortices under them, arising from underground water movements, and many are placed on alignments with other sites or at alignment intersections.
A cairn (on the right, with a modern trig point on it) on Watch Croft, as seen from downhill at Mên Scryfa. Middle, a menhir, placed to be seen from Mên Scryfa. Left, a natural crag, but energetic.
A damaged chambered cairn, Carn Mȇn Ellas, at Mayon Cliff near Sennen. The chamber was likely used for initiatory and retreat purposes, or perhaps a revered person was buried there to bless the land. You'd have to be considered a very special person to be buried in this remarkable place, and in being buried here that soul would be rendering a special service, blessing the place and the world (since Mayon Cliff has a wide-open panorama). It's likely anyone buried here would be a great druid or priestess - judging by the location
Leftovers of a kerbed cist cairn at Chy Praze, on the cliffs above Portheras Cove. Again, if someone was buried here, they would have been regarded as a special person. The Isles of Scilly can be seen from here - move away and they disappear from sight
Carn Mȇn Ellas - it has a remarkable placing and is on a major alignment from Godolphin Hill to the Isles of Scilly. Behind in the distance is Kilgooth Ust or Cape Cornwall
Cairn on top of Sancreed Beacon. If you're looking for a burial place for a great chief, this is a likely one.
Ruined cist cairn at Pordenack Point. Some cists contained relics or magical or geomantic items - not always bodies
Cairn at Botallack Common, close to Tregeseal stone circle and part of its complex. It has a cist or chamber in it - see left. This cairn might be an early cairn from the late neolithic
Chambered cairns are different. Not for burial, they served mainly as repositories and retreat places (for initiations, oracular purposes, conception, dying), and there's a likely empowerment function to them too, explained in Shining Land.
The atmosphere in the chamber can be intensely tranquil and yet charged up. These spaces were used shamanically and spiritually, as detailed in the book.
Looking out from a chambered cairn at Treen, just above Morvah. It's probable that the opening was blocked off, opened only at certain times. The objects, relics or deposits, or any person doing a retreat or a rite in the chamber would be in utter stillness and darkness, experiencing sensory deprivation and, if they were trained or in training, a consequent spiritual uplift. Below right is a picture of the same cairn from the outside
The chambered cairn on the summit of Chapel Carn Brea. This is what I'd call a geomantic cairn - definitely put there for earth energy reasons, for the benefit of the whole landscape. Whether there were items stored there or whether people went there for training, retreat or to die, the primary purpose would still have been geomantic. Mayon Cliff cairn above is another classic geomantic cairn
Inside the chambered cairn at Brane, near Carn Euny
Bosiliack Barrow, an excavated and reconstructed chambered cairn. Quite a friendly cairn, just between Ding Dong mine and Lanyon Quoit. This cairn is aligned with the Nine Maidens, Lanyon Quoit, Boscawen-ûn and Treryn Dinas. It also lies exactly aligned between Mulfra Quoit and West Lanyon Quoit
The neolithic longbarrow on Chapel Carn Brea. This goes back to the mid-3000s BCE, older than most barrows by 1,000 or more years
Ballowall Barrow at Carn Gloose near St Just, a totally unique multi-period chambered cairn overlooking the ocean, and it would have been very visible from the ocean and from Mayon Cliff, southwards near Sennen
Ballowall Barrow near St Just is unique, a multi-period cairn (late neolithic and bronze age) in a class of its own.
It has several chambers and cists and was altered and added to in stages over a few centuries.
It's in an inspiring location overlooking the ocean, with the Scillies visible 25 miles or 40km away over the sea.
Inside the chambered cairn at Ballowall Barrow
One of the Boscregan cairns, just down the coast from Ballowall. This is a propped stone inside a cairn setting - thoroughly unique and rather difficult to figure out. The Scillies are prominent from here. The group of dowsers and archaeologists behind are standing at the cist cairn above
One of the Boscregan cairns. This clifftop cairn, visible from out to sea, had a cist inside it. Chapel Carn Brea is behind
Tregiffian cairn, a chambered cairn near the Merry Maidens - part covered by a road, once an ancient track passing the barrow
Cairn with cist at Pordenack Point. Altogether there are three cairns and one circular enclosure here - plus a dramatic clifftop headland with many simulacra nearby. Pordenack Point is a more significant site than often is reckoned
Chapel Carn Brea, the last hill in Britain - it has a lot of cairns on and around it