Set dramatically beside the sea, close to John O'Groats, this 15th-century castle has a reputation for its house parties at Hogmanay, St Valentine's Day, Easter and other notable dates. With activities such as beach barbecues and ceilidhs, the atmosphere can be as wild as the scenery.

At other times, the 25 bedrooms are available for exclusive use, fully staffed, with meals cooked using ingredients from the garden and the sea.

Ackergill Tower, By Wick, Caithness (0044 1955 603556; www. ackergill-tower. co. uk). Rental from 575 per person including meals and soft drinks.

Open-house from 1,200 per person for three nights, all inclusive.

Forter Castle, Perthshire

One part Boy's Own adventure, two parts fairy tale, this pint-sized 16th-century fortress is set in Glenisla, near Braemar. It was rescued from ruin by an admirer in 1990, and revamped two years ago by his interior designer daughter. The result is one of Scotland's chicest hideaways, which sleeps 10. Forter is popular with young urbanites fleeing the city for a weekend in designer wellies. With stylish tweed furnishings, Forter fits the bill. The laird's bedroom boasts a roll-top bath and four-poster bed.

Forter Castle, Nr Folda, Blairgowrie, Perthshire (0044 7736 804426; www. fortercastle. com).

From 3, 200 per week, self-catering.

Dalhousie Castle, Edinburgh

The Ramseys of Dalhousie were in possession of this 13th-century fortress longer than any other castle-owner in the country. During its 700-year history, Dalhousie Castle has hosted all sorts of people, including Edward I of England and, conversely, a long line of Ramseys who fought against the English monarchy. Oliver Cromwell used it as his lowland headquarters in 1648, but as battles subsided so gradually did the upkeep of the building. By the turn of the 20th century it had become a school; it was converted to a hotel in the 1970s. Each bedroom is individually designed: check out the circular Dalhousie room in the tower with working steel shutters once used to defend the castle.

Dalhousie Castle, Bonnyrig, Edinburgh (0044 1875 820153; www. dalhousiecastle. co. uk).

Doubles start at 260, including breakfast.

Fenton Tower, East Lothian

The 16th century was a busy time for Scotland's castle-builders. This property, just east of Edinburgh, dates from that period, although there was already a fortress here back in the 11th century.

Restored in 1998, its six suites are classily contemporary in style, and it is surrounded by rolling fields and the sea. This is also prime golfing territory, with several top courses nearby. And enjoy the food . . . it's terrific.

Fenton Tower, Kingston, North Berwick, East Lothian (0044 1620 890089; www. fentontower. com). Suites start at 445, including breakfast.

Myres Castle, Fife

A pink, turreted 16th-century pile, this classic Scottish castle is rented out for house parties on an exclusive basis. At 45 minutes' drive from Edinburgh and 20 minutes' from St Andrews, it's easy to get to. The castle has been recently refurbished, and now boasts nine very luxurious if slightly mumsy bedrooms (Mary Queen of Scots is said to have slept in one). Expect enormous roll-top baths, roaring fires and understated chic. Guests can choose to eat the excellent meals in the Victorian kitchen rather than in the dining room if they feel like a less stately experience.

Myres Castle, Auchtermuchty, Fife (0044 1337 828350; www. myres. co. uk). From 420 per person a night, including meals and soft drinks.