Exactly one day after the inauguration of 45th President Donald Trump, thousands from around the country are expected to gather in Washington D.C. for the Women’s March on Washington in protest to Trump’s election win.

The march was the brainchild of Teresa Shook, a retired attorney and a grandmother of four, who turned to Facebook on election night to suggest the protest.

She posted the idea to Pantsuit Nation, a Facebook group in support of Hillary Clinton writing simply: “I think we should march.”

Shook initially suggested calling the event the “Million Woman March,” inspired by the historic protest by black women in Philadelphia in 1997.

That name immediately sparked criticism as many of the women who initially organized the march were white. Organizers later renamed it the “Women’s March on Washington”.

Despite the name, any person, regardless of gender identity, is encouraged to join.

Here’s a primer video by the Women’s March on the event:

Organizers say the goal of the march is to address and encourage dialogue on a range of social justice issues, from immigration, LGBTQ rights, and racism.

A long list of Hollywood stars, activists, comedians, and singers are planned to participate, as well as speakers including Angela Davis, Zahra Billoo, and Van Jones.

Here’s a list of places in Washington D.C. where the Women’s March will have special stations:

The march schedule:

Date: Saturday, January 21, 2017
Time: The rally is scheduled to begin at 10 a.m. eastern and end at 1:15 p.m. when the march begins.
Location: The starting point and rally will be the intersection of Independence Avenue and Southwest Third Street, Washington, DC, near the US Capitol. However, the route for the march is not yet determined but it will go for 1.5 miles.

Security will be extremely tight for the inauguration and the Women’s March on Washington.

The following items are banned from public events during inauguration week: ​

Aerosols
Ammunition
Animals other than helper/guide dogs
Backpacks
Bags and signs exceeding size restrictions (8″x6″x4″)
Bicycles
Balloons
Coolers
Explosives
Firearms
Glass or thermal containers
Laser pointers
Mace / Pepper spray
Packages
Structures
Supports for signs and placards
Weapons of any kind
Any other items determined to be potential safety hazards

At least 600 “sister marches”, solidarity events across the United States and the world, will also be held on this day.