system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are ancient buildings, cities and structures usually found buried underground?
gpt
Survivor bias. The interesting archeological sites are the ones that were protected by a big pile of dirt or sand. The ones that didn't get buried aren't around to look at anymore. They were sacked, demolished, renovated, or eroded. Pompei being buried in a volcanic eruption is an extreme example of this.