"Why the Amazon River Can't Be Crossed By Bridge"

CNN:

For most of its length, the Amazon isn't anywhere close to too wide to bridge—in the dry season. But during the rainy season, the river rises thirty feet, and crossings that were once three miles wide can balloon to thirty miles in a matter of weeks. The soft sediment that makes up the river bank is constantly eroding, and the river is often full of debris, including floating vegetation islands called matupás, which can measure up to 10 square acres.