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.
5. Whixley Hall - £6,000,000
Whixley Hall, in the charming village of Whixley, about 10 miles west of York, is described as 'one of the finest private houses in the north of England'. Set in around 55 acres of land, the Grade II-listed 17th century hall retains many historic features but has more recently been fitted with a bio mass boiler and craftsman-made secondary glazing to enhance its energy efficiency. It contains six good-sized bedrooms, a self-contained one-bedroom apartment, an impressive reception hall, drawing room, dining room and panelled library, plus a well-equipped kitchen/breakfast room. There are also two cottages and a number of well-maintained outbuildings, including a double-height garage block and nine stables. | Rightmove/Savills Photo: Rightmove/Savills
6. Swathgill, Hovingham - £7,000,000
Swathgill lies between the villages of Hovingham and Brandsby, within the picturesque Howardian Hills Area of Outstanding Natural Beauty, in North Yorkshire. The country estate extends to around 211 acres, with a delightful seven-bedroom Georgian farmhouse at its heart and a separate two-bedroom detached cottage. There are beautiful formal gardens, a heated indoor pool, gym and cinema room, and a set of farm buildings, and the grounds contain a mix of arable land, meadows, pasture and woods, including three ponds. | Rightmove/Savills Photo: Rightmove/Savills
7. Thornton Park Estate - £9,750,000
This vast estate between Thirsk and Northallerton, in North Yorkshire, spans around 633 acres and includes the site of the former mansion house. The estate also encompasses the Grade II-listed stable block, incorporating Park House. There are 12 residential letting properties and a mis of traditional parkland, landscaped gardens and lakes, with opportunities for development. | Rightmove/Savills Photo: Rightmove/Savills
8. Ripley Castle, Ripley - £15,000 (offers over)
This 14th century Grade I-listed castle in Ripley, near Harrogate, North Yorkshire, is looking for a new owner, having been home to the Ingilby family for more than 700 years. Highlights of this historic lakeside castle include the Old Tower, containing an oak floor which was originally part of the HMS Rose, an 18th century 20-gun frigate, and the Knight's Chamber, which is described as one of the 'most remarkable' Tudor rooms in the country. The Oval Drawing Room and the second larger Drawing Room, meanwhile, enjoy the best views over the lakes and deer park. | Rightmove/Carter Jonas Photo: Rightmove/Carter Jonas