The Neverseen's Storehouse was where the Neverseen stored prized or special objects. It was hidden behind a waterfall — with a traversal illusion of a rainbow needed to reach it. It was a part of the Lodestar Network, but was also accessible through Starstones. The Black Swan believed it had been destroyed by the Neverseen (along with the other Lodestar Network Hideouts after they had been compromised), however, this was revealed to simply be a ruse.
Sophie, Tam, and Glimmer raided it in Unlocked. They accessed it through Glimmer's Starstone, after which they needed to traverse the rainbow in order to reach it. Sophie destroyed it with an arson attack, precipitating a war with the Neverseen. She also left a drawing of a moonlark on the ground to let the Neverseen know it was her.
The Neverseen kept many things inside the storehouse. These objects include: