system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 How do people know that archaeological sites like Stonehenge and the newly announced find 2 miles from Stonehenge are ceremonial places of worship and not something else like, i dunno, a market or townhouses?
gpt
We don't really know what it was used for, but it would have taken a great deal of effort to build so we can assume it had great significance. It's aligned with the sunrise and sunset at the solstices, so it's a fair guess that some kind of ceremony took place then. If you just wanted to know when the solstices were then you could have built something much more simple. Also, there's evidence that some of the people buried nearby were from distant parts of Europe, so it seems to be something that you'd travel to visit. We might compare it to a medieval cathedral for those and similar reasons, but saying that it was a place of worship like a cathedral is mostly speculation.