This Scottish castle is set in a lush landscape of gently rolling hills with belts of sheltering trees. Yet despite the extensive views in every direction, Cassillis (pronounced “Cassles”) is virtually invisible, lost amid 235 acres of woods even though it is only seven miles from Ayr.

For £2.5 million you are effectively buying two castles. The first is a medieval tower house, five storeys high, with immensely thick walls and the Scottish corner turrets known as bartisans. The second adjoins the original fortress and is a comfortable Regency house in the castle style, built of warm brown stone. The architects are thought to have been William Burn and David Bryce, the most celebrated exponents of Scottish baronial style.

Splendid balustraded steps lead up to the front door; a further short flight links upper and lower halls, allowing you to stand grandly at the top as your guests arrive. This is the place for stout walking sticks and impressive rows of Wellington boots.

For two centuries Cassillis has served as a fishing lodge attached to the seat of the Marquesses of Ailsa at Culzean Castle. The main floor of Cassillis consists of three big rooms, beginning with an inner hall. On the right is a handsome 14ft-high drawing room, with two immense bay windows that are almost as tall as doorways.

The dining room on the other side of the hall is of equally grand proportions. Designed for large house parties, it calls for a stately sideboard and silver dishes of scrambled eggs, kidneys and sausages at breakfast time.

Behind is a butler's pantry with steps down to a large, but still feudal, kitchen realm with Victorian cooking range, servants' hall and housekeeper's room. The guest bedrooms at the top are cosy. The main bedrooms, with lofty four-posters, are in the medieval tower. This is approached by the castle's showpiece: a broad, 17th-century spiral staircase that ascends around a central hollow core, looking like a lighthouse, complete with windows.

Above the two main bedrooms stood the grand hall of the tower house. It is now divided into a ballroom decorated with Highland cutlasses, and a library where bookshelves have little leather pelmets to stop dust collecting on the books.

The River Doon flows through the grounds, providing two miles of salmon and sea-trout fishing. The stable block provides garaging; the adjoining coachhouse has four bedrooms, and the stable cottage two bedrooms.

Cassillis has been the property of the turbulent Kennedy family since the 13th century. Their history, wrote the castle historian Nigel Tranter, “was one long catalogue of violence, savagery and sudden death”.

Today Cassillis is a peaceful place where, the family land agent says, “all you hear is the sound of sand- pipers and chaffinches”. After the death of her husband in 1994, the Marchioness of Ailsa lived on at the castle until her own death at the age of 91 last year. By this time her siblings were well established in homes near by and none choose to live in the castle. Hence the rare opportunity to buy a true stately home from the family that has lived in it for seven centuries.

Fast facts

What you get: Category A listed castle, five reception rooms, 12 bedrooms, 295 acres of woods and parkland.

Where is it: Seven miles from Ayr, 42 from Glasgow and 93 from Edinburgh. Price: £2.5 million

Contact: Savills , 0131-247 3720

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