Zurich, Switzerland is preparing for the crush of 50,000 revelers expected for EuroPride, Europe's official gay and lesbian pride parade and march.

The annual festival has been held in a different European city since its 1992 premiere in London, but attendance continues to falter when compared to other giant gay prides such as Madrid's giant July parade that boasts an estimated 1.5 million or Sydney's gay Mardi Gras that draws thousands of people to its Oxford Street route party.

Last year, host city Stockholm drew an estimated 500,000 people to EuroPride on a rainy Saturday.

“It's above all a political demonstration, to defend lesbian, gay and transgender rights. But we are not just here to demonstrate, we're also going to party,” EuroPride Spokesman Michael Rueegg told AFP.

This year's theme pays homage to New York City's Stonewall Riots – often considered the birth of the modern gay rights movement – that took place forty years ago this month.

Zurich is also celebrating, adopting the gay movement's rainbow colors throughout the city. Residents recently elected their first openly lesbian mayor, Corine Mauch. Berlin and Paris voters have also elected openly gay mayors.

Gay rights opponents are also making themselves visible. Several anti-gay groups have condemned the march and plan to launch counter campaigns during EuroPride.

EuroPride 2009 “Celebrating 40 Years with Pride” takes place Friday and Saturday and includes a week's worth of cultural programming on GLBT history.