Catacombs of New York
Post Apocalypse. Exact circumstances don’t really matter, but there needs to be A) some form of warning (doesn’t need to be much, however) B) Can’t be a *no humans left* scenario, some survivors needed for good writing.
New York, London, Madrid, wherever there’s a subway system. They are going to be the best bunkers/shelters/defensible places, right? So, likely, people flock to these places. However, if it collapses/people starve/carbon monoxide leak/etc, there are going to be thousands and thousands of bodies, just in this one space. Nothing in view but bones, for potentially hundreds of metres. There could be practically an entire city’s population just in one place, and nothing but bones remaining.
Anyway, main point, this is designed for the tumblr mechanism to judge this idea and decide whether or not I should write it.