La Mancha Negra = the black stain. In Venezuela, 1989, a black gooey stain appeared on a stretch of road in Caracas not that far from its airport. At first quite small, it soon stretched to 8 miles in length. Various weird explanations were put forward, several very expensive strategies were employed making their companies a lot of money but not solving the problem.
It seems most likely that there is a simple explanation rather than the dramatic mystery that filled the newspapers at one time. This stretch of road was resurfaced not long before the black stain appeared. In hot weather the stain gets gooier, the reverse when it cools. Therefore, the tarry substance seems likely due to inadequate mixing of the material for road surfacing: a poorly carried out piece of work with said consequences.
La Mancha Negra translates to black stain and it is named for just that, a black stain that first emerged on a highway in 1986 in Caracas, Venezuela. The stain was first noticed by highway workers resurfacing the road. The stain reportedly eventually spread to a distance of about 8 miles. It is very odd that no one ever bothered to analyze this supposedly “slippery goo that had caused over 1,800 deaths and countless other injuries.”
Most people think it’s impossible for that many deaths and injuries to have been caused especially because there is no documented evidence. The black stain or goo was real and the leading theory is that it was caused by using poorly mixed asphalt concrete when the road was first constructed.