Slovenian Prime Minister Alenka Bratusek has helped lay the foundation stone for what will be the country's first mosque, 44 years after the initial request to build it was made.
Bratusek declared the move in the capital, Ljubljana, a "symbolic victory against all forms of religious intolerance", adding that Europe would not be as culturally rich without Islam.
About 10,000 people attended the ceremony on Saturday, including Ljubljana Mayor Zoran Jankovic, and a government minister from Qatar which is helping fund the project.
"We are happy to be starting this civic project in Ljubljana, which will thus become a better-known and a more pluralistic city," Mufti Nedzad Grabus, the highest representative of Slovenia's Islamic community, told the ceremony.
Building will begin in November and should be finished by the end of autumn 2016. The cost of the project, which includes a Muslim cultural centre, is $16m, 70 percent of which will be met by Qatar.
"This means the world to me," said Sahra Kacar, who was born the same year as the first official petition to build the mosque in Ljubljana was filed. "We will have a proper place to pray, rather than using various public halls."
Petition for referendum
The proposal for a mosque had been held up by reluctant local officials, some of whom tried to force a referendum on the matter in 2004.
Five years later, about 12,000 people signed a petition calling for a referendum, but once again Slovenia's Constitutional Court ruled against it on the grounds of religious freedom.
Slovenia is a Catholic country of two million people, of which about 50,000 are Muslims.
While the plan for a mosque had stirred debate, the concerns have been overshadowed by the financial turmoil facing the country.
The project comes during Slovenia's worst financial crisis since independence in 1991, which threatens to make the country the latest member of the 17-nation eurozone to seek a bailout from the EU and the International Monetary Fund.
"I personally am not against the mosque but I do know people who are still against it," said a 30-year old designer who lives near the site of the new mosque and gave her name as Ana.
"But the mosque is no longer that high on the political agenda because the attention is now focused on the economic crisis that is crippling Slovenia," she said.