It was not an easy task for a team of dinosaur-hunting scientists to reach the remote site called Jenguebi in northern Niger deep in the Sahara Desert. It was fitting that the closest locality was named Sirig Taghat, meaning "no water, no goat" in Tamasheq, the local Berber language.

But the arduous three-day off-road journey in 2022 through harsh desert terrain paid off with the discovery of fossils of the magnificent fish-eating dinosaur Spinosaurus mirabilis, one of the largest meat-eaters ever to walk the Earth.

"The heart of the Sahara - the most barren, unforgiving, yet beautiful, part of the desert," University of Chicago paleontologist and research leader Paul Sereno said.

The researchers, who had made an exploratory visit lasting less than a day to the site three years earlier, set off from the city of Agadez. There are no permanent human settlements for hundreds of miles (km) around Jenguebi.

"Jenguebi is extremely remote and isolated, and very hard to get to. It is very far from the closest cities, there are no roads that lead to the area directly, and on top of that, almost nobody - even Tuareg Berber nomads - inhabits it at any given time because of the scarcity of nearby wells," said paleontologist Daniel Vidal of the University of Chicago and Universidad Nacional de Educación a Distancia in Spain.

"It took us almost three whole days of driving off-road to get to the site, with the hardest part in the last day, having to navigate through the sand dunes with a large convoy including a large truck carrying drinking water, supplies and equipment that got stuck in the sand constantly," Vidal said. "However, any frustration or exhaustion from this long trip vanished instantly as we arrived and started discovering new fossils in no time."

The adventure was set in motion by a sentence in a scientific monograph from the 1950s in which a French geologist mentioned finding in this area a single tooth resembling that of another meat-eating dinosaur known from Egypt's Western Desert.

Sereno noted that no researchers had returned to that site in more than seven decades.

"It is an arid area with sand dunes and barely any vegetation," Vidal said. "There is only a single water well that still yields water in the vicinity. But more importantly to us paleontologists, there are large areas with patches of rock outcrop surrounded by extensive dunes, which in satellite images look like an island archipelago surrounded by a sea of dunes, which led to the nickname 'Spinosaur archipelago'."

"These rocks are very thin and soft sandstone that feels almost like compacted beach sand, and it is very rich in vertebrate fossils, particularly dinosaurs. So rich that we located more than a hundred fossil localities in under two weeks of fieldwork," Vidal said.

The researchers unearthed fossils of multiple Spinosaurus mirabilis individuals and remains of various other dinosaurs from about 95-million years ago.

"I am amazed by how Spinosaurus mirabilis left people in awe since the moment it was discovered," Vidal said.