Thousands of people are expected to descend on the nation’s capital this week to protest President-elect Donald Trump’s inauguration. 

The National Park Service has granted demonstration permits to at least 28 groups and is expecting more than 350,000 protesters. Of those, about 200,000 are participating in the Women’s March on Washington, according to Politico. In another form of protest, a growing number of lawmakers are simply refusing to attend at all.

“These are unprecedented numbers,” Mike Litterst, a spokesman for the National Park Service, told Politico.