Killerton near Exeter Devon is a large farming estate. The Acland family gave it to the National Trust in the 1940s along with their Exmoor Holnicote Estate.
Killerton was where the main house was and generations of the family lived there. If you go there today you’ll see the house nestled beneath Dolbury hillfort and surrounded by mature wooded parkland.
Killerton House with Dolbury Hill behind
In the medieval period, the old centre of the Estate lay to the west, beside the river at Columbjohn. There is still a chapel there where some of the Aclands are buried… but 250 years ago Sir Thomas Acland wanted a new grand house and shifted his home to a new location.
The chapel near the old manor house site at Columbjohn
I had a meeting a couple of weeks ago. It was to discuss the recent archaeological recording work and repair along Killerton’s scheduled park boundary wall.
When I got there I was shown a LiDAR image of the park. The amazing thing about LiDAR is that it can strip away the trees and show the archaeological earthworks hidden beneath. As the plane flies over, it fires numerous laser impulses at the ground. The first return hits the tree canopy but the second return is from the laser impulses that filter though and bounce off the ground beneath. The thing to do is to filter out the first returns and there is your picture of the archaeology on the forest floor.
The LiDAR showed something very strange in Columbjohn Wood. A big rectangular feature on the ridge top with an L-shaped feature to the west.
There was time. Friday afternoon, a bright clear winter day, leafless and no undergrowth. I set off on a ground-truthing exercise. Up past the mansion house, through the garden and the parkland edge, crossing the boundary into Columbjohn Wood. Then through the trees and along the ridge top looking at the ground beneath my feet (archaeologists tend to look at the ground).
The ditch and stone revetted boundary bank of the 18th-century deer park
Great views out to the south.. and there was the conical Mount Pleasant, which, I had been told, had the foundations of a hexagonal garden folly tower on it. Worth having a look….
…a great location and the stone footings were still clear jutting from the top of a barrow-like mound. The folly tower would once have been clearly visible in the surrounding landscape but not really from the present Killerton House.
Mount Pleasant from Columbjohn Wood with the folly mound on the top
Back down the hill and then up to Columbjohn Wood ridge again and ..there were some clay roof tiles churned up in an animal burrow and ..there was the L-shaped rampart and a large rectangular pit. A track cut close to its north side and here I bumped into a spread of brick rubble eroding out of the wheel ruts… Amongst the trees were scattered chunks of stone.
Interesting…
The site? of Sir Thomas Acland’s never completed mansion in Columbjohn Wood.
I spoke to Denise at Killerton House. She told me that it might be the house that Sir Thomas Acland changed his mind about.
1775-76: in America, the British colonists had chosen to disconnect themselves from the mother country and at Killerton, Sir Thomas had chosen the location for his new house. He appointed a fashionable architect James Wyatt and work began.
The Acland family archive contains the accounts for £1000s spent on building work.. creating the cellars and beginning to construct the walls, but something went wrong. There’s a terse exchange of letters in early 1777. Mr Wyatt was to cease all work and the builders were to leave the new site.
Everything stopped. Then the work began again in 1778-9 but at a different site and with Mr Johnson not Mr Wyatt. The accounts tell of payments to the salvage team, 33 men taking down bricks from the site on the hill and unpicking the mortar. Loading the materials onto carts to bring to the new site where Killerton House is today.
Nobody had worked out where this almost mansion was but it seems that the LiDAR has found it for us. Our big rectangular pit may be the cellars mentioned in the documents and the pile of stuff to one site may be unwanted building material left behind during the salvage work. 
Old oak at the foot of Mount Pleasant
Perhaps this 1775-6 site was a windier location… but with great views across the Devon landscape and with the hill top tower folly clearly visible in the foreground. I wonder why Sir Thomas changed his mind.
Archaeology National Trust SW 