Stonehenge is undoubtedly England's most famous prehistoric landmark. The site's first architects began work around 3000 BCE, giving way to 5,000 years of myth and mystery at Stonehenge. We know very little about the famous monument, given that its creators left no written record about it, but after a few hundred years of excavations, archaeologists have been able to piece together some of Stonehenge's story.

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You've heard the stories about the mysteries of Stonehenge's origins, but here are 10 things you probably didn't know.

10 The Site Consists Of More Than Just The Henge

Sure, the impressive stone circle at the heart of Stonehenge is what most people come to see, but did you know that the entire UNESCO World Heritage site covers about 6,500 acres across Salisbury Plain? According to the English Heritage Blog, that's 7.5 times the size of Central Park.

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Also included in the site is the henge at Avebury, a much larger stone monument, though somewhat less impressive due to its lack of massive trilithons. Both sites were listed together in 1986.

9 As Old As The Pyramids

We often think of the Pyramids as the oldest major prehistoric monument, but Stonehenge is actually just as old as its Egyptian rivals. The Great Pyramids of Giza were built during a period of roughly 85 years in 2500 BCE.

Meanwhile in Britain, Neolithic tribes were busy erecting the stone circle at Stonehenge around the same time. But some of the features of the landscape had already been made. The circular ditch around the henge was dug some 500 years earlier, and there is some evidence that there was a previous structure at the site of the current henge.

8 Stonehenge Was Built In Phases

They say Rome wasn't built in a day, and neither was Stonehenge. As previously hinted, Stonehenge was constructed in phases spanning both the end of the Neolithic Period and the start of the Bronze Age. Archaeologists have identified six stages in which the monument was erected.

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The circular enclosure surrounding Stonehenge (possibly once containing bluestones) is the oldest part, having been dug around 3000 BCE. The massive sarsen stones were then brought to the site 500 years later and stood upright to form the trilithons, forming the structure we know today. But there were still four more stages of construction after the main monument was complete.

7 Archaeologists Think It May Have Been An Ancient Concert Venue

Archaeologists and enthusiasts have speculated about Stonehenge's purpose for centuries, but aside from the usual burial ground and religious temple theories, Dr. Rupert Till believes it may have had a musical purpose.

Tourists often report of the sounds of Stonehenge, and there may be some truth to it. If it was not now in ruins, Dr. Till believes the acoustics would be amplified. Stonehenge's bluestones carry a distinctive echo, leading him to suggest that ancient peoples knew this and specifically sought out the stones.

6 Ancient People Used It As An Astronomical Tool

Stonehenge could have been used for a lot of different things, but it's eerie how accurately it lines up to astronomical events, that it could almost be compared to an ancient observatory.

The monument faces northeast, and each stone is meticulously placed for tracking the sun, especially at the solstices and equinoxes, which would have been crucial times on the prehistoric calendar. These days marked the growing and harvest seasons, and would have meant life or death for the ancients.

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Astroarchaeologists even suspect that the winter solstice would have been more important to them, as it marked the coldest and darkest day, meaning warmth and the growing season was coming.

5 Druids Consider Stonehenge Sacred

Many people believe Stonehenge was built by the Druids as a place of worship, and it does seem that whoever did build it must have had the help of some sort of magic, but the Celtic priests who brought the religion to the British Isles didn't arrive until almost 3,000 years after construction on Stonehenge started. Now can you picture how old it really is?

Although it's unlikely that Druids ever even worshiped here, modern Druids and neo-pagans consider Stonehenge a sacred site. Many take pilgrimages out to Salisbury Plain to pray or leave offerings to various deities, and the summer solstice festival is one of the largest gatherings of druids anywhere.

4 It Was Long Thought To Be A Work Of Merlin

Maybe a little more far-fetched than the Druid theory is that the stones were magically transported to Wiltshire by the wizard Merlin. Geoffrey of Monmouth, who chronicled the legends of King Arthur, wrote that Merlin airlifted the stones from County Kildare in Ireland, and placed them on Salisbury Plain as a memorial to a massacre of Britons by the Saxons.

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To a modern audience, Geoffrey's story sounds absurd, but in the Middle Ages, they had no way of explaining how the stones stood upright, and to them, magic seems like the most logical answer.

3 The First Guidebook Claimed It Survived The Biblical Flood

You'll find no shortage of strange theories about Stonehenge's architects or history, but one particularly odd statement was written in the first guidebook on Stonehenge. The book, published in 1823, was written by Henry Browne and provided an insight into the Stonehenge and Avebury sites.

One tidbit Browne decided to include was that Stonehenge was one of the few man-made sites to have survived the Biblical Flood, which wiped out humankind. The theoretical Flood would have taken place around 2350 BCE, making Stonehenge mostly complete at the time, so it's easy to understand why Browne would have made the assumption.

2 A Swiss Author Reported That Aliens Helped Build It

From the Bible to wizards, people will come up with any sort of theory regarding Stonehenge with varying degrees of rationality. One thing we try so hard to understand is just how this 5,000 year old civilization transported the bluestones all the way from Wales, and erected the multi-ton sarsen trilithons.

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Swiss author Erich von Däniken believed he cracked the code in 1968 when he published his book, Chariots of the Gods?, in which he claimed that extraterrestrial visitors either revealed enough technology to build Stonehenge or built it themselves. Many believe von Däniken's claims, although they have largely been dismissed as pseudoscience.

1 Visitors Aren't Allowed To Touch The Stones

As much as you'd like to walk within the stone circle and touch the legendary stones, as of 1977, touching the stones is strictly prohibited. The ruin is in a very delicate condition, and with the massive throngs of tourists flocking to the monument each year, constant touching could be detrimental to the preservation of this treasure.

Damage done by tourists in Victorian times, when they were permitted to hack off bits of the stones as souvenirs, has proven severe, and today, Stonehenge is roped off from visitors. Don't worry--it's still magnificent from behind the barriers.

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