Ordnance Survey Benchmarks at Stonehenge

18 11 2016

Amongst all the various carvings on the stones at Stonehenge, from the modern graffiti of the 17th to the 20th century and the ancient axe heads and daggers from about 1700BC, there are three that are not often noticed.

These are the Ordnance Survey (OS) benchmarks.

The OS website says: “Bench marks are the visible manifestation of Ordnance Datum Newlyn (ODN), which is the national height system for mainland Great Britain and forms the reference frame for heights above mean sea level.”

The original reference datum levelling survey was begun in Liverpool in 1840 using a benchmark on St. John’s Church, and in 1844 it was changed to the tidal pole in Victoria Dock. The reference Mean Sea Level (MSL) for the datum was established over a nine day period of tidal observations.

A second levelling survey was carried out in 1912-21 and the datum was changed to MSL at Newlyn in Cornwall. In the 1950s a third survey was performed, still making use of the Newlyn datum.

The OS benchmarks at Stonehenge are in the traditional form of three lines / | \ beneath a horizontal bar which is the indicator of the reference height above the datum’s MSL at that spot.

stone-16-annotatedCoincidentally, this is a similar form to that of the Druidic “Awen” emblem which also uses three lines / | \  but positioned below three dots rather than a horizontal bar. See https://en.wikipedia.org/wiki/Awen for the history and an explanation of this symbol.

At Stonehenge two of the benchmarks are on the Heel Stone and one is on Stone 16.

Stone 16 is the tooth-like stone at the southwest side of the monument directly behind the tallest stone on the site, and the benchmark is low down on the left of the southeast face.

 

This references the Newlyn datum, is 103.114m above MSL and was last verified in 1957.

The Heel Stone is the massive leaning stone some 80m northeast of the stone circle which famously (but only roughly) indicates the position where the sun appears on the horizon at the summer solstice as seen from the centre of the stone circle.

Its benchmarks are low down on the right hand side of the northeast faceheelstone-annotated

The upper one references the original Liverpool datum, is 101.346m above MSL and was last verified in 1900.

The lower one references the Newlyn datum, is 100.7m above MSL and was last verified in 1957.

From the Newlyn benchmarks, you can work out that there’s a drop of 2.414m from the one on Stone 16 to the one on the Heel Stone.

None of these benchmarks are visible from any of the visitor paths around the monument, although if the light is right (early morning or evening in summer) the upper one on the Heel Stone can just be made out from the National Trust field.

To see them properly you’ll need to come to one of the Managed Open Accesses at the solstices or equinoxes.

Alternatively, you can book a private Stone Circle Access visit which take place most days of the year before and after regular opening times.

STONE CIRCLE ACCESS

Stone Circle Access visits, give you a unique opportunity to experience up close this world famous monument. The visits take place outside of our normal general admission opening hours and are subject to very limited availability. Please note that this is not a guided tour, and touching of the stones is not permitted.  You can try Stonehenge Guided Tours for these special access tours

Article by guest blogger and local Stonehenge historian Simon Banton

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The Stonehenge Bluestones.

7 11 2016

The bluestones at Stonehenge are the smaller rocks you can see standing inside the huge sarsens that form the outer circle and the inner trilithons.

Stone 62.jpgThey range in size from stumps barely visible in the turf through to slender pillars standing nearly 2.5m tall (plus another metre or more below gound) with the largest weighing between 2 and 3 tonnes.

These rocks definitely come from the Preseli Mountains in southwest Wales, 150 miles from Stonehenge as the crow flies. Their place of origin was first established in 1923 by the geologist H. H. Thomas and has been confirmed by modern geochemical analysis. They used to be known as the “foreign stones” because it was recognised that they weren’t local to the Stonehenge area.

The name bluestone is a collective term and there are two main types – spotted dolerite and rhyolite.

It’s not obvious why they’re called bluestones to most people since at first glance, and especially from a distance, they look more greyish green in colour. But a freshly broken piece of the dolerite type reveals that the unweathered interior is a striking blue-green colour with white spots.

How and – more importantly – when and why they were brought to Stonehenge is a matter of lively debate.raw-bluestone

Being comparatively lightweight, the transportation from Preseli to Stonehenge may have been accomplished fairly simply despite the distance involved. In the 1950s a team of a few dozen teenage schoolchildren was easily able to drag a replica bluestone using rollers and a sledge, and half a dozen were able to pilot one on a raft up and down a small river with no trouble.

One theory of when they arrived at Stonehenge suggests that it was around 3000BC and that they were placed in a circle just inside the earthwork bank in the 56 sockets that are known as the Aubrey Holes. This was 500 years before the large sarsens were put up. Subsequently, this theory says, they were moved to within the sarsen monument and re-arranged at least twice.

carn-goedogThe question of why anyone would go to the bother of transporting up to 80 rocks from Wales to Wiltshire is unanswerable. It may be that they formed an existing monument that was dismantled as the spoils of war, they might represent the ancestors of a group of people who migrated eastwards or they may even have been a gift from one population to another.

They clearly had some great significance, perhaps because of their striking position in easily quarried outcrops on the top of the Preseli Mountains.

Curiously, a number of the Stonehenge bluestones were once the components of two bluestone trilithons that must have stood about 2.5m tall. The evidence is in the form of two half-buried bluestone lintels that have mortise holes worked into them and several other standing bluestones that have the remains of tenons on their tops.

These individual components are now placed remotely from each other at Stonehenge but perhaps these small trilithons were the inspiration for the enormous sarsen versions that still stand at the monument.

There are only about 30 visible bluestones remaining at Stonehenge and it is likely that the others have been chipped to pieces for souvenirs and talismen or stolen away for use elsewhere in the last 5000 years. Local rumours of bluestone doorsteps, bridge footings and magnificent fireplaces crop up every so often and fragments have been found in many of the nearby Bronze Age burial mounds.  Stonehenge special access tours allow you to enter the inner circle of Stonehenge and get close to the blusestones.

Article by guest blogger and local Stonehenge historian Simon Banton

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Stonehenge Spring (Vernal) Equinox Open Access: 20th March 2016

8 03 2016

The ‘Managed Open Access’ at Stonehenge for the Vernal (Spring) Equinox, will be from approximately 05.45 am until 08.30 on 20th March 2016

• Access to Stonehenge for the Spring Equinox will take place on the morning of 20th March 2016 (source: http://www.sarsen.org/)

The Vernal Equinox is at 04:30GMT
Sunrise will be 6.07am

Stonehenge-Spring-Equinox-2015 (60)

• Entrance to the monument will commence as soon as ‘light-levels’ are deemed safe enough to permit. For the past couple of years this has occurred around 0545h however EH would ask that people are patient should the morning prove ‘overcast’ and a slight delay occurs.

• Access to Stonehenge will cease at 0830h and the cooperation of all of visitors in ensuring the monument is vacated at this time would be most appreciated.

• Temporary toilets (Porta-Loos) will be available at the monument once the site is open for public access. This includes a provision for those with disabilities.

•The Cafe and Shop at the new Visitor Centre at Airmans Cross should be opening for visitors from approximately 0800h on the morning of 20 March. Please note that the toilets at this location will also become available for use at this time. Although the Cafe will be opening only hot and cold drinks will be available for the first hour. Pasties etc will become available after 0900h.

Final confirmation from English Heritage as to these arrangements has not been forthcoming so please check before relying on this notice.

Follow us on Twitter for the lastest news and Equinox Sunrise pics

The Stonehenge News Blog





Experience Sunrise at Stonehenge 2nd March. #Periscope Drone Live Stream

28 02 2016

LIVE! Catch the sunrise at Stonehenge. With Dan Snow #Dronehenge #Periscope.

Stonehenge is a magical place to be, steeped in mystery and History. We’re delighted that English Heritage have given us special access to film from this ancient stone circle, a UNESCO World Heritage site. Live on March 2nd from 6 am. The sunrise is at 6:50 am GMT.

dronehenge

How do we let people, a lot of people, know about a very special live event that is only happening online without a massive marketing budget? How can live streaming compete with the mass of distractions out there? There’s no TV schedule. No billboards. No iPlayer for this sort of thing.
Live streaming is special; Periscope is special because the audience is there with you. People ask Dan Snow, “Why do you Periscope? The audience isn’t massive…it doesn’t pay anything. What’s the point?”
If you haven’t watched one of Dan’s ‘scopes’ you haven’t experienced the tangible excitement ‘live’ brings to the show. It’s more than a show. From under the bow of the Mary Rose – where they installed wifi especially, to the extraordinary views at Gallipoli, scrambling through the underbrush in Harfleur in the search of Henry V’s battlements, to the cacophony on an airborne Lancaster bomber -one use in infamous Dam Buster raid.Dan Snow takes you to places other broadcasts cannot reach. 
Armed with just his iPhone and a respectable 4G signal, Dan is liberated from the traditional film crew and all that goes with that. Periscope is the app that’s made this possible – in just under a year Dan Snow has filmed almost 100 ‘scopes’ from all over the world, to a global audience.
Dan Snow is the resident ‘history guy’ for the BBC’s ‘The One Show’.
When we heard Periscope had teamed up with action camera company:GoPro we got excited. We could now ‘hand-off’ to an external camera wirelessly – our synapses began to fire.
What could Dan do with an external camera that would enhance the form? We’d seen GoPros – these matchbox-sized cameras with a high fidelity camera – strapped to skiers helmets, screwed to BMX bikes, and stuck on surfboards. What could Dan do to create stunning visuals, to enhance the story, and where should he take it?
“It’s got to be a drone, and it’s got to be Stonehenge,” said Dan, without missing a beat.
After a month of phone calls, planning, testing, tinfoil, and tech-wizardry, we’re ready. And with help from Periscope – we’re delighted that Dan will be able to do something during the live stream that would have been impossible to do otherwise! You’ll have to wait and see!
Tinfoil? Yep! The limitations of wifi range between the iPhone and the GoPro, signal frequencies of the drone (don’t cross the streams!), we’ve learned some expensive lessons. Falling down 7 times and getting up 8. After all the planning and testing we’re ready.
Stonehenge is a magical place to be, steeped in mystery and History. We’re delighted that English Heritage have given us special access to film from this ancient stone circle, a UNESCO World Heritage site. Live on March 2nd from 6 am. The sunrise is at 6:50 am GMT.
CLICK HERE FOR DETAILS
We hope you will join us on the ‘scope’. We would love it if you’d help us spread the word by joining this Thunderclap! Thank you!
Follow Dan Snow on Twitter
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Follow Stonehenge on Periscope (includes live broadcast of 2016 Summer Solstice Celebrations)
Follow Visit Stonehenge on Persiscope. 
The Stonehenge News Blog




Guided Tours of Stonehenge

18 01 2010


I am a professional tour guide who can provide ‘private’ guided sightseeing tours of Stonehenge for small groups.
I specialise in Stonehenge and ancient Britain and can often get permission from the English Heritage to take you beyond the fences and touch the Stones after the site is closed to the public. (special access or inner circle tours)

Private tours can depart from London, Salisbury, Bath or Bristol

Some of my popular ‘favourite’ day tour itineraries include:
King Arthur Day Tour
Stonehenge
Glastonbury and King Arthurs Avalon
Challice Well Gardens (reputed buriel site of the Holy Grail
Avebury Stone Circle
Silbury Hill

Great Heritage Trail Day Tour
Stonehenge
Roman City of Bath
Lacock Village
Castle Coombe

Wessex Explorer Day Tour
Salisbury Cathedral
Old Sarum Hillfort
Stonehenge
Avebury Stone Circle
Chalk Hill figures
Buriel Mounds
Crop Circles (April to Septemeber)

However, private bespoke tours can be tailored to suit your requirements and can offer the ultimate flexibility throughout your day (s) visiting almost any location you wish to visit.

I promise a well balanced day with continuous information about not only the places we visit but England in general. My style of touring guarantees an informative, entertaining day, certainly never boring.
I frequently see so called ‘professional’ guides giving an uninspired hasty tour of tourist attractions and then demand huge tips for their ‘sloppy’ services at the end of the day.
MY MISSION STATEMENT: In the unlikely event of you not being entirely satisfied with my services I will NOT charge you!

I truly appreciate that many of you will only visit Stonehenge or England once and deserve a great experience.
I can supply 100’s of testimonials from satisfied customers (individuals/ families/groups) and have a 1st class reputation with many of the UK tour operators. (my heads getting bigger and bigger the more I write) Seriously folks, give me the opportunity to quote for your private group tour (1 – 16 passangers) and I wont disappoint.
By contacting me direct you can also ‘cut out the middle man’ i.e travel agents who add a big fat commission for doing little
Direct Email: tour.guide@rocketmail.com








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