Oh, hey I recognize that technology.
Some of us called them teardrop ships, from the conical configuration of the force field over the top, and the rounded exterior for the rest of it.
The lower portion contains the anti-gravity, phase-shifting, and hyperdrive functions, as well as the dimensional adapters which power everything.
When "landing", the bottom portion is phase-shifted to allow the craft to settle into the landscape, leaving only the "hill" of the "castle" extending above.
It's an elegant way to travel, but not very practical for scientific exploration, and such ships always had all the military practicality of a barrage balloon.
The expenditure of colossal resources to manufacture such craft was only practical under conditions of extreme economic excess, but it would be perfect for a relaxed or decadent lifestyle.