ROME — It is Friday. You can see devout Muslims across the city traveling to the nearest prayer center or mosque as they do every week. Nothing new here except that we are not in the Middle East.

We are in Rome, home to Europe's largest mosque, where a couple of thousand Muslims congregate on a weekly basis. During the month of fasting called Ramadan up to 35,000 Muslims participate in prayer services here.

Nowadays, every capital city in Europe has a mosque to accommodate its growing Muslim population. Is this, as some alarmists call it, the third Muslim invasion? Is it the breeding ground for sleeper cells that might carry out terrorist maneuvers if U.S. and European forces invade Iraq? Or is it simply a fact of modern life — one more group that has been integrating into European society?

According to a recent issue of The Economist, there are 15 million Muslims living in Europe. Four million to five million live in France. Three million live in Germany. Britain has 1.3 million. The Netherlands, Belgium, Italy and Spain have a couple hundred thousand.

Massive growth of Muslims in Europe raises concerns — about how to coexist.

In reality, these numbers are difficult to calculate because not all Muslims choose to reveal their religious affiliation, not all countries ask for it and not all Muslims living in Europe are legal citizens.

“The ex-colonial powers have typically been the countries to which Muslims have migrated,” said Aziz Sheikh, head of documentation for the Muslim Council of Britain.

When asked which European countries were noting an increase in religiosity among its Muslims, Sheikh defined such an increase as a “reassertion of an Islamic identity.”

”I can only really speak about Britain with any authority,” he said. “Here we are witnessing something of a divergent trend with some younger people trying to realize what a Muslim identity means in a largely secular West, while others seem to be drifting from their Islamic roots into a materialistic-centered existence.”

Ahmad Rafat, an Italian/Iranian journalist considered to be an expert on Muslims in Europe, also noticed a trend.

“In countries where people are recently converted, they are looking for a ‘European Islam,’” he said. “For example, in Spain, many of the Muslims are Spanish. People now speak about an Islam which is closer to the West.”

It is difficult to find hard data on whether immigration is speeding up or slowing down. As Sheikh put it, “My impression is that many countries in Europe are of late trying to resist immigration from new Commonwealth countries [largely nonwhite] in response to the ascendancy of far-right movements throughout Europe. This trend has of course been accelerated by the Sept. 11 disaster.”

The Muslim community in Europe is heterogeneous at best. The only common denominator is religion because cultural and ethnic traditions vary depending on the country of origin. There is even a great diversity in how people practice, from the casual to the orthodox. This has caused many problems in terms of government relations.

“In Italy, the government has never been able to deal with the Muslim community,” Rafat said. “This is because there is no representative. There are too many groups. In contrast, the Jewish community is very united and does have a representative. This is a problem because Muslims cannot get benefits. The government wanted to give them tax deductions, which are normally given to religious groups, but there was never any consensus on whom the government should dialogue with.” The same problem exists in France, he said.

In his book Islam in Europe, professor Tariq Ramadan of the University of Fribourg, an expert on European Islam, says the first Muslims to arrive in Europe chose to protect their religious identity by being as discreet and “invisible” as possible.

Today's Muslims are much more secure in their rights as European citizens. They live their faith more publicly and without reserve. They choose to integrate within Western society without abandoning their religious and cultural identity. This is particularly true for the children and grandchildren of Muslim immigrants who are born in Europe.

“I think the majority of second- and third-generation Muslim migrants are integrating pretty well on the whole,” Sheikh said. “This is in part because of the removal of language barriers that affected many first-generation Muslims.”

“For the third and fourth generation it is much easier to integrate,” said Mario Scialoja, an Italian convert to Islam who is part of the board of administration for Rome's mosque. “The kids go to public school. They tend to assimilate well. But integration takes a long time. It is just like the Italian immigrants who went to America in the late 1800s.”

“With regards to the question of integration,” said Father Justo Lacunza, president of the Pontifical Institute of Arabic and Islamic Studies in Rome, “the process is painful in itself. You have to go slowly. There is a history, a culture of values in Europe that are based on Christianity. In spite of mistakes, it produced a great civilization.”

Though the cultures might be different between the West and Middle Eastern countries, according to Father Lacunza, Muslims choose to move to Western Europe, the United States and Canada if given the opportunity.

Among the ongoing problems Muslims face in Europe, Sheikh cited “racism and religious discrimination, social exclusion and negative stereotyping in the media, which do not help matters.

“We do of course have some fringe groups who continue to receive a disproportionate amount of media coverage,” he said. “Of course, Muslims have been deeply hurt by 9/11 and the subsequent diatribe that has been launched against the teachings of Islam.”

There has been some concern that Muslim immigrants will somehow imperil Europe's Christian identity. Some people do convert to Islam, but it is a very small minority. The concern is, rather, how to learn to live with a new group.

“The question is alarmist,” said a Vatican official, who asked not to be identified. “One must photograph reality and look at the real problems.”

Though Italians worry that in 50 years Muslims will outnumber Catholics in the country (Catholic Italians have few children and Muslims seem to have more), the Vatican official said the decreasing birthrate and unemployment have other causes.

“The question of Muslim immigrants should not be used for political ends,” he said. Muslims, in other words, are only deemed a problem when used as the scapegoat for real social issues in Europe.

“People who fear Muslims are above all people who do not know them,” said Rafat, the Italian/Iranian journalist. “If 1% of Muslims in Italy are radical, it gets pushed to all of them. The ignorance factor plays a great part.”

Sabrina Arena Ferrisi writes from Rome.