Cornish monument is 4k years older than was thought and 'without parallel'
theguardian.com
theguardian.com
The Kennet Long Barrow is similar age, shape and construction:
https://en.wikipedia.org/wiki/West_Kennet_Long_Barrow
Similar barrows exist across southern England, and in the wider Atlantic coast region, from Spain to Brittany and Ireland:
https://en.wikipedia.org/wiki/Cotswold-Severn_Group
The only unusual about King Arthur's Hall is the apparent absence of burial chambers.
https://en.wikipedia.org/wiki/Cunetio
https://en.wikipedia.org/wiki/River_Kennet
That's assuming yours isn't from something unrelated such as Kinnettles in Scotland.
unrelated, you mean, to Mildenhall in Suffolk, because isn't a word from Cornwall more like than that to be related to a Celtic language name?
I'm not sure which two of the three things (Kinnettles, Mildenhall, and Cornish names) you're comparing. If you're saying it's outrageous to find a Celtic place name in Suffolk, you're right, except this is a name from Roman times, when Romans were Romanizing Brittonic Britons and the Anglo-Saxons hadn't yet got a look in. And river names tend to be the oldest names and full of debated and unexplained elements, such as the "Or" in Orwell, and the Ouse.
To paraphrase Sheldon’s joke - Archeology is a science of “what did I just trip over”.
I am joking. Enjoy your cornish wonder of the world :)