Most of these mega mansions will be out of the reach of ordinary house hunters but they show what you could get if you have a few million pounds to spare.
From a 14th-century castle to a striking modern silo conversion, these properties are all truly unique and are priced from £4 million to £15 million.
Most boast extensive grounds, beautiful landscaped gardens and glorious views over the surrounding countryside.
As well as charming period features, they have plenty of modern touches, including cinema rooms, gyms, swimming pools and air conditioned wine stores.
Below are the nine most expensive mansions listed for sale on Rightmove, from the lowest to the highest priced.
For more amazing properties, take a look at these houses for sale on Britain’s most expensive streets.
1. The Silos, Swinton Grange - £4,250,000
This truly unique home in Malton, North Yorkshire, was converted from a series of former grain silos. Floor to ceiling windows make the most of the beautiful views of the landscaped gardens and surrounding countryside. One of the cylinders houses a bespoke fitted oak library. The property also has an EPC rating of 'A' 124, meaning it is 24 per cent more efficient than the highest UK efficiency rating. | Rightmove/Savills Photo: Rightmove/Savills
2. Highwood House, Moor Lane - £4,500,000
This modern country house in Gilling East, near York, has six bedrooms, six bathrooms and four reception rooms, and boasts outstanding views of the rolling hills surrounding it. It includes a leisure suite with swimming pool and gym, a games room, a cinema room with bar, and an air-conditioned wine store. | Rightmove/Croft Photo: Rightmove/Croft
3. Brackenthwaite Lane, Pannal - £4,500,000 (offers over)
This collection of barns near Harrogate, North Yorkshire, was lovingly converted in 2013 to a stunning country house. Between them, the barns contain seven bedrooms and eight reception rooms, and they boast beautiful panoramic views. | Rightmove/Strutt & Parker Photo: Rightmove/Strutt & Parker
4. Thorney Hall Estate, Spennithorne - £5,000,000
This 60-acre country estate boasts superb views from its elevated position in Wensleydale, near Leyburn, North Yorkshire, looking across to Richard III’s Middleham castle and the hills of the Yorkshire Dales National Park. It has a third of a mile river frontage and fishing rights for the River Ure. Thorney Hall includes multiple reception rooms, four kitchens and 14 bedrooms across the main house and two self-contained accommodations, The Grange and The Dairy Cottage. | Rightmove/Strutt & Parker Photo: Rightmove/Strutt & Parker