Explorer travels Britain to document more than 400 mysterious little known pre-historic sites

This standing stone can be found on the remote Isle of Harris, part of the Scottish Hebridean islands and home to fewer than 2,000 people.

This prehistoric monument stands at 39 feet (1.86m) tall and was thought to be part of a stone circle, due to several other stones that were found nearby. 

The site faces the northern Atlantic ocean to the west, which may have held some symbolic importance to its builders.

This site is approximately 26 miles (43km) south south west of the Callanish Standing Stones on the Isle of Lewis.

Bryn Cader Faner is a Bronze Age cairn, a mound of rough stones built as a memorial or landmark, typically on a hilltop or skyline.

It lies to the east of the small hamlet of Talsarnau perched atop a mountain and resembles a crown of thorns made out of rocks.

Fifteen stones, up to six feet (2m) tall, survive in this cairn circle, with the central cairn measuring 28 feet (8.5m) across and rising just three feet (1m) high. 

It is believed to date to the third millennium BC and as many as 30 stones may once have stood at the site.

 The three standing stones of machrie moor can be found in one of the largest areas of level ground on the Isle of Arran off the western coast of Scotland.

This rich archaeological landscape also includes stone circles and burial chambers, all dating to between 3500 and 1500 BC.

The stone circles were preceded by elaborate timber circles placed at exactly the same location. 

They were associated with religious activities dating back around 4,500 years, including cremation and burial rites.

The Callanish stone circles can be found on the Isle of Lewis in the Outer Hebrides archipelago off the coast off Scotland.

It originates from the late Neolithic period 5,000 years ago and has three sets of stone circles – each being within a mile or so of each other.

They predate England’s famous Stonehenge monument, and were an important place for ritual activity for at least 2,000 years.

Experts believe they were used as a pre-historic astronomical observatory. 

Avebury is the world’s largest prehistoric stone circle and was excavated by archaeologist Alexander Keiller in the 1930s.  

They were first built and then altered during the Neolithic period, roughly between 2850 BC and 2200 BC.

The henge survives as a huge circular bank and ditch, encircling an area that includes part of Avebury village.

 The original henge was comprised of about 100 stones which in turn enclosed two smaller stone circles.

Between 1973 and 1976, reservoir was constructed by Welsh Water to regulate the flow of the river Dee. 

As a result of this disturbance of the landscape archaeological investigation of around fifty sites in the valley was carried out. 

The majority of sites excavated were of bronze age date although a camp used by mesolithic hunter gatherers was also discovered. 

This is dated by radiocarbon analysis of the charcoal from their fires to around 5,700BC.

There are few stone circles in Britain in such a dramatic setting as that of Castlerigg, overlooking the Thirlmere Valley with the mountains of High Seat and Helvellyn as a backdrop.

It is potentially one of the earliest in the country and is thought to have been constructed about 3000 BC.

The entrance is flanked by two massive upright stones, and the outlier is presently to the west-south-west of the stone circle, although it has been moved from its original position. 

It has been suggested that such outlying stones had astronomical significance, perhaps alignments with planets or stars.

The Thornborough Henges are located near the village of Thornborough, in North Yorkshire and are thought to be between 5,000 and 6,000 years old.

They are part of an area known as the Vale of Mowbray which is a location known for its concentration of Neolithic and Bronze Age monuments. 

There are no less than six giant henges, all almost identical in size and design, located within 6.2 miles (10km) of one other. 

It is the world’s only triple henge complex and the three henges follow the same off-centre alignment seen at other triple-circles across England.

The giant 4,500 year old Rudston Monolith in north Yorkshire is 25ft (7.5 metres) tall, towering over the graves in the churchyard where it can be found.

It is the tallest prehistoric standing stone in Britain, standing almost 26 feet (8m) high, nearly 6.5 feet (2m) wide, (1m) thick and weighing somewhere in the region of 26 tons.

This giant block of grey sandstone or gritstone was quarried 10 miles away at Cayton Bay and was brought here either in the late Neolithic or early Bronze Age.

The Norman churchyard of All Saints that it stands in is of course some 3000 years younger although the Christianisation of this raised site probably took place much earlier.

Hollingbury Hillfort is considered one of the great Iron Age Hill Forts in Sussex.

It was built in around 250 BC and at one time a defence wall, made of timber with a deep ditch in front of it, made it unassailable without ladders.

A bronze brooch from the third century BC was found on an early settlement site at Kemptown in nearby Brighton.

A Hill-Fort was built in the Iron Age at Devil’s Dyke, also nearby, to provide security for local people.

Stoney Littleton is a fine example of a chambered long barrow built during the Neolithic period, around 4000 to 2500 BC.

It likely dates from around 3500 BC and is roughly 100 feet (30 metres) long.

It features multiple side chambers in which human remains were once buried. 

The approach to the barrow – down a long narrow lane, across a stream and through fields – takes visitors across a landscape that has probably been farmed continuously since Neolithic times.

Stonehenge was built thousands of years before machinery was invented.

The heavy rocks weigh upwards of several tonnes each.

Some of the stones are believed to have originated from a quarry in Wales, some 140 miles (225km) away from the Wiltshire monument.

To do this would have required a high degree of ingenuity, and experts believe the ancient engineers used a pulley system over a shifting conveyor-belt of logs.

Longstone, Mottiston Down on the Isle of Wight is located  

Legend has it that St Catherine and the Devil had a contest to see who should control the Isle of Wight. 

The burial mound has been damaged over the years and the stones themselves may have been moved in Saxon times.

In Saxon times – 4,000 years after the Neolithic long barrow was built – the Long Stone is thought to have been used as a meeting place where judicial and administrative affairs were carried out.  

The Langdale axe industry is the name given by archaeologists to specialised stone tool manufacturing in England’s Lake District during the Neolithic period.

The site was originally found by chance in the 1930s.

Site turned up axes, rough-outs and blades created by large lumps of the rock. 

The stone axes from Langdale have been found at archaeological sites across Britain and Ireland.  

It is an English Heritage scheduled monument and has been described as Devon’s finest stone circle. 

Estimates for the original number of stones are as high as 60 or 70 but it only has a diameter of 27 metres.

Today 23 of the remaining 34 stones remain in the circle.  

It is an English Heritage scheduled monument and has been described as Devon’s finest stone circle.

Midhowe Broch is a well-defended Iron Age settlement on the Orkney islands. 

It stands along the banks of narrow, dangerous Eynhallow Sound in Orkney.

A water tank, fireplace and room partitions are all still visible. 

It is on the Island of Rousay and was likely surrounded by sizeable settlements.