Reuters:

Several hundred thousand people are expected to march through Paris on Sunday against the planned legalisation of same-sex marriage in the first mass protest against the unpopular President Francois Hollande.

Strongly backed by the Catholic hierarchy, lay activists have mobilised a hybrid coalition of church-going families, political conservatives, Muslims, evangelicals and even homosexuals opposed to gay marriage for the show of force.

So many are expected to converge on Paris from around France that police had organisers split it into three separate columns starting from different points around the city and meeting in the Champ de Mars park at the Eiffel Tower.

... Gay marriage opponents such as Cardinal Andre Vingt-Trois, head of the Catholic Church in France, have asked why Hollande is pushing through a divisive social reform called "marriage for all" when voters seem more concerned about "jobs for all."

Vingt-Trois spearheaded the opposition with a critical sermon in August. Other faith leaders -- Muslim, Jewish, Protestant and Orthodox Christian -- soon spoke out too.