Celebrities show solidarity with Women's March

Actress America Ferrera speak to the crowd during the Women's March on Washington, Saturday, Jan. 21, 2017 in Washington. (AP Photo/Jose Luis Magana)

Actress America Ferrera speak to the crowd during the Women's March on Washington, Saturday, Jan. 21, 2017 in Washington. (AP Photo/Jose Luis Magana)

Scores of celebrities attended marches in Washington and other cities Saturday joining millions of people across the country in a show of solidarity with the movement bringing attention to women's rights the day following President Donald Trump's inauguration.

Photos: Women march around the world

Madonna, Julia Roberts, Scarlett Johansson, Cher, Alicia Keys, Emma Watson and Patricia Arquette joined an estimated 500,000 participants at Saturday's Women's March in Washington.

>>Read Women's March in Washington: Live updates

Cynthia Nixon and Whoopie Goldberg joined a crowd of protesters at Trump Tower in New York.

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Joseph Gordon-Levitt posted an image of himself at a march in Los Angeles, where organizers said about 750,000 people attended, according to the Los Angeles Times.

The Associated Press contributed to this report.