954 would become the Marbella Club, an international resort of movie stars, business executives and the nobility. Both these resorts would be frequented by members of European aristocratic families with well-recognized names: Bismarck, Rothschild, Thurn und Taxis, Metternich, de Mora y Aragon, de Salamanca or Thyssen-Bornemisza, transforming Marbella into a destination for the international jet set.
Given Alfonso's maternal membership in Spain's titled aristocracy (his mother, María de la Piedad de Yturbe y Scholtz-Hersmendorff, was the Marquesa de Belvís de las Navas), and his paternal kinship to the royal courts of Europe, the hotel quickly proved to be popular with vacationing members of Europe's social elites for its casual but discreet luxury. Jaime de Mora y Aragón, a Spanish bon vivant and brother to Fabiola, Queen of the Belgians, as well as Adnan Khashoggi and Guenter Rottman, were frequent visitors.
Typical was a gala held in August 1998 as a fundraiser at the Marbella Club for an AIDS relief NGO. Prince Alfonso presided, supported by the sons of his first marriage to Princess Ira von Fürstenberg, an Agnelli heiress who arrived with her own entourage; Princess Marie-Louise of Prussia (great-granddaughter of Kaiser Wilhelm II) who, with her husband Count Rudolf "Rudi" von Schönburg–Glauchau, would eventually take over the Marbella Club Hotel from Prince Alfonso; and socialite Countess Gunilla von Bismarck.
In 1974, Prince Fahd arrived in the city after having broken the bank at the Casino ofMontecarlo. Until his death in 2005, he was a frequent and profligate guest at Marbella, where his retinue of over a thousand people spending petro-dollars was welcomed, including the then-anonymous Osama bin Laden.
In the eighties, Marbella continued to be a destination for the jet set. However, the city was cast in an unflattering light in 1987 when Melodie Nakachian, the daughter of local billionaire philanthropist Raymond Nakachian
