Dublin (AFP) - Irish voters turned out in force Friday for a historic referendum on whether same-sex marriage should become legal, after a campaign that has exposed divisions in the traditionally Catholic nation.
After 15 hours of voting, the ballot boxes were sealed at 10:00pm (2100 GMT) across the republic, with polling stations reporting higher-than-expected voter numbers.
Allowing gay couples to wed would be a seismic change in a country where homosexuality was illegal until 1993, and where abortion remains against the law except where the mother's life is in danger.
State broadcaster RTE said polling stations were recording a higher turnout than usual for referendums, with voting levels in cities such as Dublin, Limerick and Waterford predicted to top 60 percent.
It said large numbers of young voters were noted across the country, with queues stretching outside some polling stations during the early morning and late evening peaks.
More than 3.2 million people were eligible to vote. Counting was due to begin at 9:00am (0800 GMT) Saturday, with the result expected later that afternoon.
In a sign of how much interest the referendum has attracted, the government announced that the 2,000-capacity grounds of Dublin Castle would be open to the public to hear the official result announcement.
"It's a very historic day, for Ireland, for gay people and for their family and for their friends, and for the future of the country," said Seamus Wright, who went to vote in central Dublin with his partner John O'Sullivan.
"Today in fact is our first anniversary of our civil partnership and we hope it's our last anniversary as well because we would like to get married," he told AFP.
At a polling station in the south Dublin suburb of Milltown, Rachael Stanley, 60, said she voted "No" and felt "strongly about it".
"It's far too radical a step. I want to protect marriage and the stability of children," she told AFP.
"I hope I don't get tarred and feathered for saying that," she added.
- Church's historic influence -
The Yes Equality group, the driving force behind the "Yes" campaign, thanked all those that voted and noted the strong turnout.
"The marriage equality movement has ignited the imagination of a people to have an active part in the Ireland they want to live in and be proud of," said its co-director Brian Sheehan.
If the move is approved and the ensuing legislation is passed, Ireland would become the first country to make the change following a popular vote.
It would be the 19th country in the world to legalise gay marriage, and the 14th in Europe.
Across the border in Northern Ireland, gay marriage is banned even though it is legal in the rest of the United Kingdom.
All Ireland's main political parties, including conservatives, supported amending the constitutional definition of marriage.
Around Dublin and other cities, lamp-posts were festooned with colourful, emotive placards for the "Yes" and "No" camps.
The final opinion polls before the vote put the "Yes" camp in comfortably in the lead but the result is by no means certain.
The Catholic Church campaigned strongly for a "No" vote, and many older and rural voters agreed with the clergy.
The majority of Irish people identify themselves as Catholic, although the Church's influence has waned amid growing secularisation and after a wave of child sex abuse scandals that badly discredited the hierarchy.
- U2 backed Yes vote -
Voters living abroad travelled home to have their say in the referendum.
A group of around 30 Irish living in London arrived on the ferry into Dublin in high spirits, carrying banners and balloons and singing Elton John's hit "Are You Ready For Love".
"For my numerous friends who are in the gay community, I felt it was very important that I added to the 'Yes' vote. I want to live in a country that values equality," said broadcast journalist Sarah Duffy, 27.
Voters were asked whether or not to add an article to the Irish constitution saying: "Marriage may be contracted in accordance with law by two persons without distinction as to their sex."
The "Yes" side was boosted by the support of Irish sports, music and film stars including Hollywood A-lister Colin Farrell.
Rock band U2 posted a social media picture of a handwritten note reading "In the name of love... vote Yes".