The Nyos disaster is a terrific and unprecedented environmental tragedy that took place on Thursday, 21st of August, 1986, at 9pm. This is a synopsis of highly specialized scientific research, information in newspapers, documents and articles in specialized media, information from the radio, the television or oral literature from concerned scientists, anthropologists, sociologists or victims that are directly linked to this geo-hazards that killed thousands in Nyos. The goal is to pay tribute to the victims of this devastating happening and insinuate lessons on how to avoid such a disaster. If hypercapnia could be incriminated in this incident, it is but evident that the meromicticity of the lake was already a great danger for the national and international community. Can early warning signais, degasification, delimitation of a security belt around the lake unravel this puzzle ? Lake Nyos is a suitable candidate for a UNESCO world heritage site.