PARIS -- It's a sight that would shatter most Americans' romanticized image of Paris.

Just a 15-minute metro ride from the trendy shops and quaint cafés of the Champs-Elysees, a virtual sea of North- and West-African Muslims spills out the gates of a neighborhood mosque. Like waves breaking on a beach, their bodies bend in unison as hundreds of men prostrate themselves before Allah. Their prayers are guided by an imam's Arabic incantations.

The crowd's prayer rugs cover a city block's worth of sidewalk. Tourists point and take pictures. Some French pedestrians are visibly uncomfortable as they negotiate their way around the assembly.

But the scene isn't an aberration. Instead, it's evidence of a trend that's changing the way Southern Baptists view the international mission field: Islam is expanding across Europe.

From Cross to Crescent

Fueled by immigration and high birthrates, the number of Muslims on the continent has tripled in the past 30 years, making Islam Europe's fastest growing religion. While European Muslims build mosques and win converts, European Christians (excluding evangelicals) are witnessing what's been called a near free-fall decline in church attendance.

Tourists make up the overwhelming majority of those crowding Notre Dame in Paris, snapping photos during Mass as if the cathedral was more museum than place of worship. Even more alarming are statistics that only 5 percent of the French own a Bible and 80 percent have never even touched one. The shift is so dramatic that many demographers now believe more people in Europe practice Islam than Christianity.

No one knows exactly how many Muslims call Europe home since most European nations don't track ethnicity or religious affiliation in census data. Guesses put the number around 20 million.

France accounts for the highest concentration of Muslims in the European Union -- 5 to 6 million, or about 8 percent of the population. Many entered the country as immigrants in guest-worker programs following World War II, but untold numbers have flooded France and other European nations illegally.

Striving for Acceptance

While the French government has made strides to help Muslim immigrants integrate into French society, things haven't always gone smoothly.

In 2004, a law banning Muslim girls from wearing head scarves in French public schools ignited an uproar among immigrants. A year later, riots broke out in Muslim-majority areas of Paris after the deaths of two North African teenagers. The summer of 2007 saw peaceful but public protests by West African immigrants in a dispute with the French government over papers that would allow them to remain in France legally.

Such tension drives some immigrants away from their Muslim heritage while others gravitate toward it.

Osman* is among the men worshipping outside the Paris mosque. Handsome and energetic, the 20-something works as a technician for the city's water department. Born in Paris, Osman's parents are Christians who came to France nearly 30 years ago from Togo, West Africa. But after years of struggling to assimilate into French society, Osman finally found acceptance among other West African immigrants by converting to Islam.