Thousands of people hit the streets in cities across the United States and beyond to celebrate science and censure disregard for knowledge.
Earth Day demonstrators held rallies across the country from Boston to Chicago to Syracuse on Saturday.
Although the organizers claimed that the march was non-partisan, it was mostly attended by activists opposing President Donald Trump.
The president, who is a climate change skeptic, recently cut federal science and research budgets, outraging scientists and science lovers.