Late Jurassic · 150 million years ago
What you're walking through
150 million years ago, western North America was a wide floodplain with long dry seasons, crossed by rivers that flooded in the wet ones. Conifers, ferns, cycads and ginkgoes grew thick along the water. There was no grass yet, and not a single flower.
This is the world of the Morrison Formation, whose rocks hold some of the biggest animals that ever walked on land. Giant sauropods moved between the river forests in herds, browsing as they went.
Who lives here
Apatosaurus
Up to 22 m long · plant eater · 152–151 million years ago, North America
One of the giant long-necked sauropods, as heavy as several elephants. It swept its neck low over ferns and horsetails, and probably used its whip-like tail to warn off predators.
Stegosaurus
About 9 m long · plant eater · 155–150 million years ago, North America and Europe
Two rows of tall plates ran down its back, and four long spikes armed its tail. Its head was small and low, made for cropping plants close to the ground.
The plants are simple stand-ins for the real Jurassic flora, and the animals are stylized low-poly models.
How to walk
Press Start walking above. WA SD or the arrow keys move you, the mouse looks around, Shift runs and Space jumps. Look at an animal to see what it is. Esc pauses, and M turns the sound on or off. You're invisible: nothing here can see you.
Other times
4 billion years ago
Early Earth
Lava fields and smoking volcanoes, under falling meteors and a huge Moon. Nothing is alive yet.
70 million years ago
Late Cretaceous
Flowering trees and palms, with T. rex, Triceratops and Parasaurolophus.
20,000 years ago
Ice Age
Snowy steppe and pines, with woolly mammoths and saber-toothed cats.