Long barrows either contained wooden or stone burial structures beneath the barrow and the surviving megalithic stone in the latter means that they are the ones referred to by archaeologists as chambered. This distinction may have been more to do with the availability of local materials however than any cultural differences.
They are concentrated in southern Britain and parts of northern England.
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It is situated, like the Toots longbarrow and Hetty Peglar's Tump, not at the very top of the hill but just below the crest of the slope so that when it was first built it would have been visible as a bump outlined against the sky from the valley below.
It is a chamberedbarrow with a false entrance at the larger northern end.
The actual burial chambers, four in all, are located on the long sides of the mound and in the tail.
The barrow at Nympsfield is a sad ruin today, the mound is almost totally gone, only a slight rise and the suspicion of the horned forecourt remain.
The layout of the burial chambers is still evident, a three chamber, cruciform, transepted arrangement.
The covering mound was carefully constructed with internal stabilising walls and a perimeter revetment of drystone walling.The barrow seems to have avoided major destruction until quite recently, surviving the middle ages thanks to the belief that it had been a leper house.