"Here, among seemingly unending geological strata, we can gaze into what the natural philosopher John Playfair called ‘the abyss of time’, a description he made after he, James Hall and James Hutton in 1788 observed layered geological aeons in the rocky outcrops of Scotland’s Siccar Point – a revelation that would eventually lead Hutton to become the founder of modern geology. In the Rift Valley, this vertical, tilted way of seeing is all the more powerful because the story of the Rift is the story of all of us, our past, our present, and our future."

https://aeon.co/essays/the-rift-valley-tells-the-entire-human-story-from-the-start