So what do we know about this civilization? Let's go to the Thought Bubble. Everything we know about the Indus Valley Civilization comes from archaeology, because while they did use written language, we don't know how to read it, and no Rosetta Stone has thus far appeared to help us learn it. I meant the other Rosetta Stone Thought Bubble. Yeah, although come to think of it, either would be acceptable. So here's what we know. They had amazing cities.