By Imogen Foulkes
BBC News, Geneva
There are just four minarets across Switzerland
On Sunday Swiss voters will have their say on a controversial proposal to impose a constitutional ban on the building of minarets.
The proposal is backed by conservative Christian groups and by the biggest party in Switzerland's parliament, the right-wing Swiss People's Party (SVP), which says allowing minarets would lead to the Islamisation of the country.
There are an estimated 400,000 Muslims in Switzerland, most from the former Yugoslavia or Turkey. Islam is the country's most widespread religion after Christianity, but although there are Muslim prayer rooms, proper mosques with minarets are few and far between.
There are just four across Switzerland, and in recent years, all applications to build minarets have been turned down.
Fear of extremism
Although there is little evidence of Islamic extremism in Switzerland, supporters of a ban say the presence of minarets would represent the growth of an ideology and a legal system that are incompatible with Swiss democracy.
The campaign in favour of a ban paints a sinister picture of Islam
"The minaret is not an innocent building. It has been used in history to mark territory, to mark the progression of Islamic law in foreign countries," said member of parliament Oskar Freysinger.
"Islamic people say it's only decorative. I don't agree. If Prime Minister Erdogan of Turkey says 'the minarets are our bayonets' that means something to me. I don't want his bayonets to be planted here in Switzerland."
At public meetings to discuss a ban, this argument has clearly found favour with some voters.
"I'm not against Islam as a religion, I'm just against the minaret as a symbol of their power, taking over, conquering," said one woman.
"I'm a believer, I'm a Christian and I'm not against the Muslims," insisted one man. "But I'm not for the power, that they put their rights, the Sharia, over the rights that we have here in Switzerland, the law."
These arguments have caused a great deal of frustration among Switzerland's Muslim community, who insist that all they want is a recognisable mosque.
Earlier this month, Muslim prayer rooms across Switzerland opened their doors to the public, in the hope of reassuring voters that they had nothing to fear from minarets.
"Countries which restrict freedom of worship" - the Swiss flag is in the middle
"We view the minaret as a symbol of religious freedom," said Mahmoud El Guindi, of Zurich's Islamic Centre.
"There is sometimes some fear in society, of Islam or the Muslims, based on various political events... and when they come here and they talk to the people and put their questions, they can see that Islam is a peaceful religion like other religions."
But a highly visible campaign in favour of a ban paints a very different picture of Islam.
Minarets like missiles
Posters have appeared in many Swiss cities showing a dark, almost menacing figure of a woman, shrouded from head to foot in a black burka. Behind her is the Swiss flag, shaped like a map of the country, with black minarets shooting up out of it like missiles.
There is also an online game, which has proved very popular, in which players can shoot down minarets as they rise up on the skylines of Switzerland's major cities.
And although few in Switzerland would question the country's system of direct democracy, in which the people vote on all major decisions, many Swiss are very uncomfortable with the tone this particular campaign has taken.
Vehicle for prejudice?
Elham Manea, a Swiss citizen and a Muslim, believes an opportunity to have a meaningful debate about Islam and its integration in Switzerland has been missed. Instead, she says, it has become a vehicle to express prejudice.
"In this debate, the very fact that you belong to a certain religion turns you into something bad," she says.
"They are bringing all these issues; integration problems, political Islam, fear of social change and social demographics, throwing them into one basket, calling it Islam and Muslims are bad.
"That is scary, because we have history to warn us when it comes to discrimination and discriminating against certain groups."
Outside Switzerland, observers are watching the minaret debate with concern. Amnesty International this week called on Swiss voters to reject a ban, warning that forbidding minarets would be a violation of Switzerland's obligations to uphold freedom of religious expression.
And there are hints that some Muslim countries, with whom Switzerland traditionally enjoys good relations, may even boycott the country if a ban is approved.
They are particularly angry that Islam has been singled out, since Sikh temples and Serbian Orthodox churches have recently been built in Switzerland, while synagogues have been present for more than a century.
Switzerland's coalition government is urging voters to say no to a ban, fearing a yes vote could harm the country's image abroad and cause anger among its many different ethnic groups.
But at the moment opinion polls predict a close result, and many in Switzerland fear that whichever way the final vote goes, the very fact that this referendum was held at all - and the tone of the campaign - will leave a legacy of bitterness among Swiss Muslims.