Highway 431, Alabama. This US highway, situated in Alabama, runs is a 353 mile stretch of road which runs from Alabama to Tennessee. It has been nicknamed the “Highway to Hell” and is thought to be one of the most dangerous roads in the world. The main issues on this road are poor visibility as well as lanes which reduce from 4 to 2 without warning. In 2014 highway 431 saw the fourth most amount of deaths of any road in America.