Workers construct an avenue, named Liberdade, or Freedom, ahead of the COP30 U.N. Climate Summit on March 18 in Belem, Brazil. The annual UN climate conference, known as COP30, will take place in Belem, Brazil, this Novemeber. The Associated Press

BELEM, Brazil — In the run-up to the annual U.N. climate conference, set to take place in Brazil’s Amazon in November, the construction of a road is drawing attention, with critics arguing it will lead to environmental degradation.

Before the talks, called COP30, the state government of Para is building a 8-mile avenue designed to ease traffic on a major highway that runs parallel.

The road was planned long before Belem, a metropolitan area of 2.5 million people that sits on the edge of the Amazon, was chosen as conference host. That hasn’t spared it sharp criticism, however, because the road is expected to cut across the last remnants of rainforest in Belem.

Road building in the Amazon, which historically has often led to deforestation and development of surrounding areas, also stands in stark contrast to a central aim of climate conferences, and in particular this one: conservation of biodiversity.

Brazilian President Luiz Inacio Lula da Silva, who has made the slowing of deforestation a central focus of his administration, has frequently boasted that this will be the first such conference in the Amazon rainforest.

Workers construct an avenue, named Liberdade, or Freedom, ahead of the COP30 U.N. Climate Summit on March 18 in Belem, Brazil. The Associated Press

The Amazon is key to regulating the climate, because trees absorb carbon dioxide, a greenhouse gas that heats the planet when released into the atmosphere.

“We will hold the best COP in history because the topic of all the ones held in other countries was the Amazon,” Lula said while visiting Belem worksites in February. “This one will be in the Amazon.”

An official project map shows a straight line dividing a green area through the city’s outskirts. This protected area is slightly larger than Manhattan. It was designated in 1993 to protect two lakes, a river basin and to restore a degraded rainforest. However, its rules allow private properties, government-approved deforestation and public works. Two university campuses are located within its limits.

“Even with measures to reduce the damage, there are tough issues to address,” said Roberta Rodrigues, a professor of architecture at the Federal University of Para. “It’s hard to imagine a road being built along the banks of the Guama River without it leading to illegal development. It may lead to the end of this protected area.”

Construction workers make progress in Belem, Brazil, Sept. 24, 2024, on a project for the COP30 U.N. Climate Summit. The Associated Press

People ride bikes near signage for the upcoming COP30 U.N. Climate Summit on March 23 in Belem. The Associated Press

People look out at the coast of Belem, Brazil, as a boat nears shore, March 23, 2025. The Associated Press