The palace is on the World Tree
At the entrance to the garden, there was an arch that checked people and vehicles to make sure they weren't getting in with anything dangerous, Mu Liang had to hand over his space item for verification.
Fortunately, his space ring was only presented to the verification system as a common accessory, if not, how could he account for so many strange things inside the space ring, things that theoretically shouldn't exist in this universe.
There were two more arches that had the verification system, before Mu Liang could finally see the structure of the palace, he thought the garden was ridiculously large.
"Below the Garden are the hangars of the security ships and where the Mechas of the imperial guards are there too," Alessandra-066 said, noticing the half-elf's change of mood.