I would like to receive the latest property news and guides, every Wednesday by email

register with your social account or click here to log in

You already have an account. Please log in

The new Lord Harlech, Jasset Ormsby Gore, 30, has a plan. He wants to sell the contents of Glyn Cywarch, a secluded 17th-century house in north Wales, known simply as “Glyn”, so he can convert it into a posh B&B.

Given that his mother is the stylist Amanda Harlech, known for collaborations with John Galliano and Karl Lagerfeld, the end result is likely to be very posh indeed.

Ormsby Gore, the seventh baron Harlech, inherited Glyn last year on the death of his father. Death duties in the Fifties saw off the family’s stately pile in Shropshire but they moved much of its contents to Glyn, set among waterfall-strewn woodland in Snowdonia.

The sale of almost 550 lots includes a library of historic books (the earliest dated 1477), a truly magnificent, recently identified portrait by Elizabethan master Marcus Gheeraerts the Younger (lot 36, £60,000-£80,000), and tons of fine old oak furniture.

The new Lord Harlech , Jasset Ormsby Gore

Estimates are sensible — though in many cases, Harlech provenance will add value. There’s a fabulous set of 19th-century kitchenalia, including copper saucepans bearing the Harlech H and a coronet — lot 25, estimated at £100-£150.

The wide selection of good, solid furniture includes oak coffers and chests, and a surprising array of tables: gatelegs, Pembrokes, sofa tables, small occasional tables and an amazing Charles I (10ft) refectory table for the ultimate dinner party — lot 35, £8,000-£12,000.

Designer: Lord Harlech's mother Amanda Harlech ( Getty )

There’s an “important” set of seven George III giltwood armchairs with hand-worked upholstery at £50,000-£80,000 but there are many more affordable things, such as a pair of Regency ebonised gilt and cane chairs at £500-£700 (lot 47); or a charming, pink, velvet-covered Italian 19th-century sofa, lot 92, for £500-£700; or the stunning tester bed with unusual curved canopy. Delicately turned and carved, this sweetheart, lot 458, is estimated at £2,000-£3,000.

£500-£700: a pair of Regency ebonised gilt and cane chairs (lot 47)

Then there is the library, an important sale on its own. More than 300 historic books, this collector’s dream includes the 1612 first collection of Edmund Spenser (lot 352, £1,000-£2,000), and Buffon’s wonderfully illustrated Natural History of 1785 (lot 368, £600-£800).

The auction has a fun side, too, reflecting the sixth baron’s skill with, and passion for, cars. He evidently had a great eye for a classic. In his gatehouse he had not only a super-rare 1936 Lagonda Rapier (only 300 were ever made; lot 537, £20,000 -£25,000) but also a thrillingly rangy 1925 Douglas motorbike (lot 538, 33,500-£4,500). A remarkable sale, and for car-lovers the Lagonda will be on show.

The Contents of Glyn Cywarch: The Property of Lord Harlech is at Bonhams London on March 29.

£2,000-£3,000: tester bed with unusual curved canopy (lot 458)

THE WAR HERO, AMBASSADOR AND LOVER OF JACKIE K

A star lot, number 194, the Kennedy-Harlech papers, tells some of the story of David, the remarkable fifth Baron Harlech. As young David Ormsby Gore he was in “Phantom” reconnaissance in the Second World War, before being made British Ambassador to Washington by his family friend, US President John F Kennedy.

Romantic link: Jackie Kennedy and the fifth baron

Ormsby Gore’s good advice helped defuse the Cuban Missile Crisis. After JFK’s assassination, the now Baron Harlech (whose own wife had died) corresponded romantically with Jackie Kennedy, until she married Aristotle Onassis. The poignant, unsent draft of his letter, when he knew he’d lost her, is in this lot. He next set up and ran Harlech TV (the hugely successful HTV).

The lot includes many personal letters, written and received, personalised invitations to the White House, even the ambassador’s embossed dispatch boxes.

The estimate is £100,000-£150,000, but that’s no surprise for such a truly historic and personal collection.