Millions of people around the world took part in Friday's climate strike, and estimates of total crowd sizes are still rolling in — some as high as 4 million.
From New Delhi to Antarctica, protesters marched to draw attention to the climate crisis ahead of the United Nations Climate Action Summit, which kicks off Monday.
In New York City, where schools excused the city's 1.1 million students from class to participate, Mayor Bill de Blasio put preliminary crowd estimates at 60,000. Organizers, however, have pegged that number at closer to 250,000, making it the largest protest that day.
Local officials and protest organizers offered varying crowd size estimates. According to organizers, some of the other largest demonstrations took place in Berlin (270,000), London (100,000) and across Australia (about 100,000 protesting in Melbourne, organizers say).
In the U.S., big groups also turned out in San Francisco (40,000), Denver (7,500) Boston (7,000), Chicago (3,000), Portland (2,000) and Washington, D.C., among other cities.
You may like: 6 things to know about teenage climate change activist Greta Thunberg
Greta Thunberg, the noted 16-year-old Swedish environmental activist who sparked the global movement, joined the strike in New York City. She and other organizers have estimated the worldwide crowd size at 4 million.
"Around the world today about 4 million people have been striking," Thunberg said. "This is the biggest climate strike ever in history and we all should be so proud of ourselves because we have done this together."
She's likely right — preliminary estimates suggest that Friday's strike was the largest climate protest in history.