This piece is meant to be listened to from under the large oak tree at the corner of Robinson, Broad and the Science Museum’s Front Circle. Pause this audio, walk to that location, and start it to take a walk through geologic time.

From where you’re standing, the intersection of Broad Street and Terminal Place is about 460 feet away.

If this distance represents the age of the Earth, every 10 feet—or about 4 steps—equals about 10 million years of Earth’s history.

The total journey, walked in a straight path by the average adult, would take about 184 steps.

You’re standing at the start of everything, 4.6 billion years in the past. The early Earth is a treacherous place, newly formed from the agglomeration of space dust and gas spinning around the young Sun.

About 3 or so steps ahead of you, our Moon forms from a collision between the proto-Earth and a planetoid about the size of Mars.

Life appears about 36 steps in front of you. It’s rudimentary at first, but the spark has been lit.

Photosynthetic organisms begin to produce oxygen around 80 steps in front of you. This sets the stage for animals to grow larger and more complex, initiating a rapid bloom of biodiversity.

Dinosaurs evolve and go extinct in the span of just 8 steps in the small plaza before you reach the intersection at Broad and Terminal.

Humans evolve within the last half of an inch of the curb, a tiptoe from the street corner. The Declaration of Independence was signed less than a human hair’s thickness away from the edge of the curb.