Just over 10 weeks after the idea was first proposed in a Facebook post, tens of thousands of protesters are heading to the nation's capital for the Women's March on Washington on Saturday.

Similar marches are planned in more than 600 other cities and towns around the world. But the largest is expected to take place in Washington, D.C., less than 24 hours into the presidency of Donald Trump.

Organizers are expecting around 200,000 marchers to gather on the National Mall. To accommodate the throng of visitors, Washington's Metro subway system will add trains and open two hours early — at 5 a.m. — on Saturday.

A four-hour rally is expected to kick off the march near the National Museum of the American Indian. It will feature speeches by Angela Davis, Gloria Steinem and the mothers of Trayvon Martin and Eric Garner, as well as musical performances by artists including Janelle Monáe, Maxwell and the Indigo Girls.

While the initial idea was formed as a protest of the presidential election results, organizers say the march is not all about Trump. Instead, they say they're marching to remind the country about the need to expand and protect the rights of all women. Their demands span from paid family leave and affordable access to abortion and birth control to accountability in cases of police brutality and a higher minimum wage.

Besides a debate over policy issues, the march has also generated a discussion about race and feminism.

"This march was initially put together by white women, and a lot of women of color felt they weren't part of the conversation," explains Carmen Perez, one of the march's national organizers who has been highlighting challenges specifically facing women of color, including those in the immigrant and LGBT communities.

There has been some pushback against the organizers' emphasis on race, and some participants say they have decided to drop out of the march in protest. But Perez says she and other organizers hope discussing racial inequities will encourage marchers to find common cause with activists of different backgrounds.

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