The property that we are spotlighting this month is quintessential London: Mayfair location, Hyde Park-adjacent, and possessing an illustrious history with royal connections. Today, this palatial Park Street mansion boasts 8,435 sqft of living space stretched across four floors, five bedrooms and four reception rooms. In decades gone by, however, these walls housed illicit marriages and international diplomats.

Built in 1778, the property was originally the home of Maria Fitzherbert, longtime mistress of the Prince Regent, later King George IV. She had married a wealthy landowner in 1778; when he died he left her the Park Street mansion, which had served as their marital home. A few years later, Fitzherbert was introduced to George; in 1785 they secretly married in the first-floor reception room at Park Street.

The marriage was later rendered invalid under English law because the king, George III, had not consented to it, and George Junior was forced to marry his cousin, Caroline of Brunswick. Fitzherbert, however, remained his “wife of [his] heart and soul”, and by 1798 he had abandoned Caroline and returned to Fitzherbert. Following the death of George IV, she told his brother, King William IV, about the secret marriage; to bury a potential scandal, William offered Fitzherbert the title of Duchess but she refused, asking only permission to dress the servants at Park Street in royal livery. Following Maria’s death in 1837, the mansion was demolished – the destruction of any architectural relic to the late King’s marriage would have been, one assumes, a relief to the Royal Family.

The current Edwardian building was built in 1913 – construction was delayed by World War I so it wasn’t ready for occupation until 1925. In 1931, the mansion was purchased by Sir Louis Bernhard Baron, a wealthy British tobacco tycoon; when he died his wife sold the Park Street mansion to the newly-formed Government of Cyprus, and it served for many years as the Embassy for the Cyprus High Commission. When this relocated to St James’s Square, the property reverted to private ownership, and is now being offered for sale on a freehold basis – which is exceptionally rare for Mayfair.

Today, Park Street may not be the locus of scandals and politics, but it remains a landmark building, with cavernous room sizes and soaring ceilings. Period features include parquet flooring and stone fireplaces, which are paired with luxurious details like coffered ceilings, passenger lifts and a sweeping main staircase. The master bedroom occupies the entire second floor, while the main bedroom boasts three sets of French windows, which open onto ornamental balconies. On the lower ground floor, there is a professional chef’s kitchen.

Design house Casa E Progetti has been commissioned to dress the house, settling on a classic contemporary style, with 1930s artwork, opulent furniture pieces from the likes of Ralph Lauren and Lalique, and Art Deco accessories like the pair of bronze greyhounds standing guard in the hallway, or an Egyptian obelisk in the ground floor reception room.

It’s fun and bold – bordering on kooky – while retaining the traditionalism and sense of rich history that oozes from this property. A fascinating proposition, and one that is sure to reel in some big-ticket buyers.

The Park Street mansion is for sale for £25,000,000. Visit wetherell.co.uk

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