Autumn Season - The Aston Martin DB4 GT
You don't have to get the James Bond DLC pack to own your own Aston Martin in Forza Horizon 4. You can get the DB4 in the autumn season. The barn hint circle should appear after a couple hours of play, south of the festival. Look for the large pond at the west part of the hint circle. Simply drive north of the pond about 100 yards to find the barn.
Summer Season - The Peel P50
This ultra compact car unlocks in summer. Using the Gables House south center of the map as a reference point, head slightly northeast. You'll find the barn nearby in the wood closest to the house.
Winter Season - The Land Rover Range Rover
The winter barn is a unique challenge, since it's on the largest island in the middle of Derwent Water. Normally you'd sink if you tried to reach it, but in winter you have a frozen lake solid enough to cross.
Spring Season - The Ford GT40 Mark I
When spring has sprung, it'll be worth the wait. This classic normally costs 9 million credits, so it makes for a hefty auction payday if you're not a Ford GT fan. You'll find this in the Moorhead Wind Farm - to be precise, it's in the open area immediately north of the first 'O' of the Moorhead map text.
Bamburgh Castle - The Bentley Blower
This antique is the reward for buying the 10 million credit Bamburgh Castle on the east coast of the map. It's in the middle of the coast. Just look for the castle with the For Sale sign. After the sale, head south along the coast to find the barn. It's hidden in a wood, about equidistant from the castle and the Thatch Corner house.
As for the two remaining barns, their purpose hasn't been determined yet but we suspect they're being saved for a future DLC-related event. We will update this guide as soon as further information is available.
[mystery barn 1]
One of the barns can be found at the far northwest corner of the map. Drive to the open area in between Mortimer Gardens and the Glenfinnan Viaduct. Avoid the nearby highlands as the barn is closer to sea level.
[mystery barn 2]
The other mystery barn is on a hill sandwiched between two creeks at the southern coast, south of the Thatch Corner house. The barn is located where the open area meets the trees.
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