An illegal dirt road ripping through protected areas in the Brazilian Amazon is now just a few miles shy of connecting two of the worst areas of deforestation in the region, according to satellite images and accounts from people familiar with the area. If the road is completed it will turn a large area of remaining forest into an island, under pressure from human activity on all sides.

Environmentalists have been warning about just this kind of development in the rainforest for decades. Roads are significant because most deforestation occurs alongside them, where access is easier and land value higher.

On the east side of the new road is a massively-deforested area where Brazil’s largest cattle herd, 2.4 million head, now grazes. This municipality of Sao Felix do Xingu is the country’s second-largest greenhouse gas emitter, thanks to deforestation, according to Climate Observatory, a network of environmental groups. It is roughly the size of Maine and has a population of 136,000.