Where Is ‘The Most Dangerous Place In The History Of Planet Earth?'

apparently it was the Sahara desert, but why?

perhaps this picture, the title and cation might give you a clue, Predator paradise - The giant predatory dinosaur Carcharodontosaurus eyes a group of Elosuchus - crocodile-like hunters - near a carcass. Artwork by Davide Bonadonna, from the article,

'About 100 million years ago, the area was home to a vast river system, filled with many different species of aquatic and terrestrial animals. Fossils from the Kem Kem Group include three of the largest predatory dinosaurs ever known, including the sabre-toothed Carcharodontosaurus (over 8m in length with enormous jaws and long, serrated teeth up to eight inches long) and Deltadromeus (around 8m in length, a member of the raptor family with long, unusually slender hind limbs for its size), as well as several predatory flying reptiles (pterosaurs) and crocodile-like hunters. Dr Ibrahim said: "This was arguably the most dangerous place in the history of planet Earth, a place where a human time-traveller would not last very long."

so if someone does ever invent time travel, this is not the era to visit the Sahara!