Barrows are Neolithic tombs, often called burial mounds, which are scattered throughout Britain. Wiltshire County, in particular, is home to 148 of Britain's 260 barrows. There are two primary types of barrows: long barrows, which were designed for communal burials and round barrows, which are smaller and designed for individuals.
West Kennet Long Barrow
The most famous of these is the West Kennet Long Barrow, constructed in 3,650 BC, making it older than nearby Stonehenge and Avebury. In fact, it's the oldest and longest barrow in England.
The West Kennett Barrow is 350 feet long and 75-50 feet wide. There are 5 chambers, two on either side of the passage, and one at the end, opposite the entrance.
There were 46 known burials here, including both adults and children, before the tomb was sealed with giant sarcen boulders about 2,200 BC, which as it happens, is about the time Avebury was being constructed.
Normanton Down Barrows
The barrows of Normanton Down (near Stonehenge) are also well known, and most resemble huge mounds strategically aligned in the flat fields. These were built between 2,600-1,600 BC, after the construction of Stonehenge, and contain both Neolithic and Bronze Age burials.
There are both long and round barrows at Normanton Down, and more than a few of the round barrows included cremated remains. Weapons and jewelry have been found at the sites suggesting that only those of high social status were buried here.
Leylines are hypothetical alignments of important monuments, and are often said to follow energy patterns from the earth. It's interesting to note that nearly all of Britain's barrows are associated with established leylines.
For more information, please see the following links:
Etva's Wiltshire County Series
Stonehenge (3,100 BC)
Old Sarum (3,000 BC)