It’s probably as revolutionary and groundbreaking as Mozart gets these days. A German-based quartet staged Saudi Arabia’s first-ever performance of European classical music in a public venue before a mixed-gender audience.

The concert, held at a government-run cultural center, broke many taboos in a country where public music is banned and the sexes are segregated even in lines at fast-food outlets.

The Friday night performance could be yet another indication that this strict Muslim kingdom is looking to open up to the rest of the world.

A few weeks ago, King Abdullah made an unprecedented call for interfaith dialogue with Christians and Jews — the first such proposal from a nation that forbids non-Muslim religious services and symbols.

“The concert is a sign that things are changing rapidly here,” German Ambassador Juergen Krieghoff said. His nation’s embassy sponsored the concert as part of the first-ever German Cultural Week in Saudi Arabia.

“Evidently the government has decided that a minimum of openness in our new world economy and in our information-based world is necessary for us and also for good understanding among cultures,” the ambassador added.

Public concerts are practically unheard of in the kingdom. Foreign embassies and consulates regularly bring musical groups, but they perform on embassy grounds or in expatriates’ residential compounds, and the shows are not open to the public.

In the past couple of months, however, there has been a quiet, yet marked, increase in cultural activities in Saudi Arabia. Lectures and a couple of segregated folk music performances were held on the sidelines of Riyadh’s book fair. And Jiddah’s annual Economic Forum opened with a surprise this February: a performance of Arab and Western music.

“For half an hour, we did not quite know whether we had stumbled into an unknown Jiddah nightclub or whether it was some amazing mistake that would suddenly stop,” Michel Cousins wrote in the English-language daily Arab News, describing the 30-minute show.

Friday’s concert of works by Mozart, Brahms, and Paul Juon was the first classical performance held in public in Saudi Arabia, German press attaché Georg Klussmann said. It was advertised on the embassy’s Web site with free tickets that could be downloaded and printed.

The excitement in the 500-seat hall was palpable as the largely expatriate audience walked in.

“We have not done a concert like this before,” German diplomat Tobias Krause told the audience at the start of performance by the Artis Piano Quartet. Those gathered applauded enthusiastically after each piece and were treated to an encore.