Wherever you are in Britain, you're not more than a couple of hours from something thousands of years old. Here are 15 of them, ranked from "newest" (everything's relative) to oldest.
1. Caerleon amphitheatre, South Wales, 74AD:
The best-preserved Roman amphitheatre in Britain. It would have seated 6,000 spectators – an entire Roman legion.
2. Prysg Field Barracks, South Wales, 74AD:
Just next door to the amphitheatre at Caerleon is the only remaining Roman legionary barracks in the world.
3. Broch of Mousa, Shetland, 100BC:
A "broch" is an Iron Age Scottish tower, and the broch on Mousa, one of the Shetland islands, is the largest and most spectacular. It's 13 metres tall, three times the height of a double-decker bus, and impressively intact after more than two millennia.
4. British Camp hill fort, Malvern Hills, 200BC:
An extraordinary Iron Age fort, once home to hundreds of people, but which fell into disuse – perhaps destroyed by the invaders – around the Roman conquest of Britain.
5. Wittenham Clumps hill fort, Oxfordshire, 1000BC
The twin hills of Wittenham Clumps – also known, oddly, as Mother Dunch's Buttocks – were first occupied a thousand years before the birth of Christ. They were abandoned 400 years later, until the Roman invasion. The inset is an aerial shot by Major George Allen from 1939.
6. Silbury Hill, Wiltshire, 2400BC:
The largest man-made mound in Europe, built around the same time as the Pyramids – and of similar size to some of them. There is no body buried in it, as far as archaeologists have been able to tell, and no one knows what it was built for.
7. Ring of Brodgar, Orkneys, 2500BC:
A huge stone circle surrounded by 13 burial mounds on Mainland, the largest Orkney island.
8. Avebury stone circle, Wiltshire, 2850BC:
The vast Avebury monument, about 30km from the better-known Stonehenge, is probably older, and in some ways is more impressive, than its more famous neighbour. It comprises a great earthwork ditch and wall, known as a henge, about 420 metres in diameter. Inside that is a stone circle 330 metres across; within that are two smaller circles. Some of the stones are more than 5 metres tall; the largest is estimated to weigh more than 100 tonnes. No one knows exactly why the circles were built.
9. Barnhouse Settlement, Orkneys, 3000BC:
Not as well preserved as their near-contemporaries at Skara Brae (below), these Neolithic huts may have been deliberately demolished when their inhabitants left. Two of the 15 buildings are much larger and more impressive than the others, and may have belonged to someone of great importance, or perhaps had some ritual significance.
10. Skara Brae, Orkney, 3180BC:
A huge storm battered the Orkney islands in 1850, tearing great chunks of turf from a strip behind the beach on Mainland, and revealing a strange group of buildings. It wasn't until the 1970s that it was confirmed that these buildings were more than 5,000 years old; they are the best-preserved group of Neolithic dwellings in western Europe.
11. Midhowe Chambered Cairn, Orkneys, 3500BC:
The most magnificent and best-preserved of 15 ancient tombs on the isle of Rousay in the Orkney islands, Midhowe is more than 30 metres long. Nine complete corpses, three disembodied skulls, and the scattered remains of another 15 people were found in the cairn when it was unearthed in the 1930s.
12. West Kennet Long Barrow, Wiltshire, 3600BC:
A huge 100-metre-long burial chamber for around 50 people, 1,000 years older than Stonehenge itself, and a vital archaeological site filled with the stuff of Neolithic British life.
13. Knap of Howar, Orkney, 3700BC:
These two oblong stone buildings – a dwelling and a workspace – are perhaps the oldest still-standing houses in northwest Europe. They were occupied for around 500 years, until 3100BC.
14. Parc Cwm long cairn, Gower peninsula, 3850BC:
While the Parc Cwm cairn itself was built a mere 5,850 years ago – a burial site for at least 40 people – the ground it is built on appears to have been occupied for at least 5,000 years before that, since Britain was in the grip of the last Ice Age.
15. Maiden Castle hill fort, Dorset, 4000BC:
A 6,000-year-old castle atop a hill, one of several Neolithic hill forts in Dorset, and one of the most complex in Europe. By the time the Pyramid of Giza was built, Maiden Castle had been continuously occupied for almost 1,500 years. The inset shows an aerial photo of the fort, taken in 1939 by Major George Allen.
Tom Chivers is a science writer for BuzzFeed and is based in London.
Contact Tom Chivers at firstname.lastname@example.org.
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