As you can't see, the Citadel in this room is Absent.
Nevertheless, the immense length of the Chain it was made for can be seen!

Alex's Chain Fortress
https://dopcom.net/creechers/p/room/OqnOACPi

chakhatic's Rare Citadel of the Chain of Creation
https://dopcom.net/creechers/p/room/QWHhACTO

Donut's Loud Temple of the Chain of Cold
https://dopcom.net/creechers/p/room/lS4-ACT8

folk's Chain Citadel
https://dopcom.net/creechers/p/room/F66xACRz

starryrainz's Dark Atrium of the Nameless Chain
https://dopcom.net/creechers/p/room/Yfu_ACUu

thunderzizi's House of the Prismatic Chain of Adequate Life
https://dopcom.net/creechers/p/room/Y9baACUy

shmewtep's House of the Chain
https://dopcom.net/creechers/p/room/ghUVACPi

BlueTinge's Common Locus of the Chain
https://dopcom.net/creechers/p/room/18iiACRz

tinytoes's Studio of the Chain of Victory
https://dopcom.net/creechers/p/room/Da7oACU2

limikun's Cabin of the Hollow Chain of Power
https://dopcom.net/creechers/p/room/NUBhACU3

wit's Prismatic Workshop of the Radiant Chain
https://dopcom.net/creechers/p/room/VoInACR0

Hypercube34's Atrium of the Chain of Light
https://dopcom.net/creechers/p/room/qCk5ACVF