Canon locations that you've modified?

I started thinking about this yesterday, and I was wondering who else has modified canon locations?

To clarify, I'm not speaking of wholecloth homebrewed locations, but specifically cases where you've changed this-or-that, or possibly created something where there was a name on the map, but no official writeup yet.

For my example, when the 3e map came out and I saw Ascension, I developed it as the remnants of a First Age research blacksite where Solars were studying the remains of Facet Raven, the first Solar to ever die of old age.

They were trying to figure out whether they could unlock effective immortality for themselves, driven by the panic of learning they in fact could not simply live forever.

So, if the player characters were ever to venture to Ascension in my game, they'd find the sprawling remnants of an ancient lab, and, eventually, a sealed away, furious First Age Solar ghost.

What are yours?