The nine-day convention was being held as a side event to a U.N. sustainable development summit in Rio de Janeiro, where more than 100 world leaders were trying to forge a path to international development while protecting the environment.
The alternative event, funded by the Brazilian government, drew about 15,000 people a day, according to organizers. It focused the frustration of indigenous groups, environmental activists, unions, land rights groups and others over the alleged timidity of proposals coming out of the official convention, and over international failure to act on commitments made 20 years ago at the first Earth Summit.
While the official convention center is far from downtown Rio and requires a credential to enter, the People's Summit was open to all, offering discussions on topics such as the link between women's reproductive rights and the planet's health, and recycling efforts run by former trash pickers.
Performance art included indigenous chants with participants in traditional garb and modern dance by youth in minimal clothing and body paint.
The movement spawned two marches on Wednesday that drew tens of thousands each. One protested the removal of the community of Vila Autodromo to make way for projects connected to the 2016 Olympics. The other opposed alleged capitalist appropriation of the official Earth Summit.