How do I find the citadel

it’s my first game but I’ve been playing it for quite a long time. But I’m stuck at the point where I have to destroy the Citadel (Pandoran). But how do I find it? I’ve got almost all the Phoexik bases with satellites everywhere and I still can’t find it anywhere.

Can you please advise me

when you will discover some Nests and Lairs don’t destroy them. Defend everything around them, and let them evolve into Citadel. It may take some time.