Millions of people across the country are expected to join in protest this weekend against Donald Trump’s administration, a movement intended to coincide with the president’s planned military parade in Washington — and the commander-in-chief’s 79th birthday.

The movement, explicitly anti-Trump and anti-authoritarianism, is encouraging cities nationwide to organize and demonstrate on Saturday.

Thousands took to the streets for the ‘No Kings’ protest across the U.S. Here’s what we know about the turnout and the movement’s message.