Head out of London on the M40 motorway, branching left onto the A40 at Junction 8, alternatively if you stop at the adjacent Oxford services for provisions you can still get you access to the A40. Use this road to head into the Cotswolds where a lot of Downton filming took place. Branch off left for Witney on the B4022 and follow the brown signs for Cogges Farm Museum. The Cotswolds is limestone country and has similarities to Yorkshire where Downton Abbey is set. So this area doubles for Yorkshire as the Cotswold region is unspoilt, full of old buildings and nearer to the London studios.
As you approach the edge of Witney there are two signs for Cogges, the first left takes you to the parking area for larger vehicles and the second left down Church Lane takes you right into the farm and should fit a camper van though spaces are limited. Cogges Manor Farm is a working farm museum, complete with goats, ponies and chickens, old farm machinery and a dairy, and has a lot to offer families of all ages. There's a play area, cafe and kitchen garden to explore. Some parts of the grand Manor House date back to the 15th century, but for fans of Downton Abbey the buildings should be immediately recognised as Yew Tree Farm where Timothy Drewe looks after Marigold, the illegitimate daughter of Lady Edith. The farm had a new tenant by the end of series six, Mr Mason and his daughter-in-law, Daisy.
You'll be able to see the interior where Mr Drewe and his family lived, watch a specially recorded film about the making of Downton Abbey at Cogges Farm and see the yard and driveway where Robert, Cora and Edith come racing down when Mr Drewe's wife Margy abducts Marigold from the local fair. The thatched ox barn at the front of the farm has a well stocked gift shop which includes Downton souvenirs!
From here head back to the B4022 and turn left into Witney, leaving the town on the B4047 passing the old blanket mill, now converted into private apartments. Witney was famous for blanket manufacturing from the 17th century until the 1980s. This road will take you towards the A40 but just before you reach the roundabout branch off right down a single track road that takes you into the valley of the River Windrush towards the village of Astall. Here you can visit St Nicholas's Church. In the third episode of Series 1 Matthew visits the interior of this church, showing more interest in its architecture and less interest in Lady Edith, who thought she might replace her sister in his affections, but to no avail.
Asthall Manor, the house that stands next to the church was the childhood home of the famous (and infamous) Mitford sisters, Nancy, Jessica, Unity, Deborah, Diana and Pamela. All finding their own way in a world between the wars, politically and socially, and sometimes to great controversy.
If you drive past here to the next village of Swinbrook you'll arrive at the Swan Inn. Just remember to turn right at the cricket field. There is a car park at the back and the pub does great food. It is also where Tom Branson and Lady Sybil stop overnight on their way to elope to Scotland.
You can loop around the village then drive back up out of the valley to the A40. Take a left then immediate right to leave the A40 following signs to Brize Norton. After half a mile you will see a right hand turn for Shilton. Turn here and follow the road straight into the village. You will cross the A4020 just before entering Shilton then drive through the village and at the far end you will see a pond, a ford and the little village war memorial. Park here. The building next to the ford was transformed into the Red Lion pub in the Yorkshire town of Kirbymorside. In episode 4 of series 2 Anna gets the bus here to find Bates working in this pub.
From Shilton drive out of the village up the hill along the attractively named Hen 'n' Chick Lane, past the telephone box, now a mini-library! Turn left at the top and drive through Alvescot and Black Bourton to the town of Bampton which doubles for Downton village in the series.
Bampton has become incredibly popular since the film crews first arrived here in 2010 to transform the houses clustered around the church into Downton village. Surprisingly to some people Bampton is much larger than what appears on screen and the town does boast a supermarket, post office, pubs and restaurants. But that's in a part of the town where none of Downton was filmed. You need to head to St Mary's Church, appropriately located down Church Lane.
St Mary's doubles up for St Michael and All Angels in Downton Abbey. Matthew, Sybil and Lavinia Swire lie buried in the churchyard. Inside the church you can see where Mary married Matthew, Edith was jilted by Sir Anthony Strallan, where Mary married her second husband, Henry Talbot and Edith finally walked down the aisle with Bertie Pelham. Not forgetting the wedding of Charles Carson and Elsie Hughes.
Churchgate House next to St Mary's doubles for Mrs Crawley's home, the village green is where the War Memorial would be, Mr Moseley lives in one of the terraced houses on the other side. Further down Church Lane is the Post Office, the Dog and Duck pub and Mrs Patmore's Bed and Breakfast, which is supposed to be in a completely different town, Haughton-le-Skerne!!!
The main draw here is the Bampton Archive, housed in the same building as the town library. This is the site of the Cottage Hospital in Downton village. Pop inside to see an exhibition on the filming of the TV series here and buy some unique Downton souvenirs!
There now involves a drive out of the Cotswolds southwards to Highclere Castle which doubles for Downton Abbey itself. The B4449 heading south east of the village to the A415 is the road that will take you there. As you continue on the A415 through Kingston Bagpuize you can pause at Kingston Bagpuize House, this doubles up for Cavenham Park, home of Lord Merton until his marriage to Isabel Crawley.
Eventually you will arrive at the A415 and A34 junction. Take the A34 south over the rolling Berkshire Downs for about half an hour or so until you see the signs for Highclere Castle. Don't follow the earlier signs simply for Highclere as that will take you to the village not the house. The Highclere Castle signs will also lead you towards Burghclere. Look for the sign for Burghclere and Ecchinswell, turn left down Harts Lane into Burghclere. Here, next to the church, you will find Portal Hall, used as Downton village school where Daisy sits her exams and where Carson and Mrs Hughes have their wedding reception.
Turn back around on Harts Lane and drive straight on for about 2 miles (3km) and then take a right turn up the driveway to Highclere Castle, home of the 8th Earl of Carnarvon. Designed by the architect Sir Charles Barry and built between 1839 and 1842, its construction coincided with his most famous design, the Palace of Westminster, also known as The Houses of Parliament. But to the fans of the life and times of the Crawley family, this is Downton Abbey, this is the highlight of the trip!! The grounds and gardens will be instantly familiar. Once inside you can see Lord Robert's library, the dining room, sitting room and the bedrooms. View the entrance hall and grand staircase. The servants bedrooms and the kitchens were actually done in the studios in London so the basement here at Highclere won't reveal Mrs Patmore busy at work but will contain an exhibition on the 5th Earl of Carnarvon and Howard Carter's journeys to Egypt and the discovery of the tomb of Tutankhamen.
Nevertheless, there is a lot of Downton Abbey scenes filmed both in and out of the house within this vast estate of 6,000 acres, 1,000 acres of which were beautifully landscaped by Lancelot "Capability" Brown. You can see where Lady Mary fell off her horse, where Bates was tripped up in the very first episode, where Barrow and O'Brien have their cigarette breaks and gossip, then you can wander inside the house where a great many memorable scenes have taken place, not to mention some of Violet's very best lines!!!!
Leaving Highclere you can return to London by taking the A34 back up north to Newbury then joining the M4 east to London.