Within the interior is a level, featureless floor.

Only a few tiny craterlets mark this otherwise featureless floor.

This is a circular crater with a low outer rim and a level, featureless interior floor.

The inner walls slope down to a featureless inner floor.

Spinner, gazing down, couldn't tell how far away the nightblack, featureless floor was.

The inner walls are simple slopes that run down to the relatively level and featureless floor.

It is a circular, bowl-shaped formation with a almost featureless interior floor.

The interior has been resurfaced by lava, leaving a nearly flat, featureless floor.

The interior has been resurfaced with lava, leaving a flat and relatively featureless floor.

Everything was metal - a flat, featureless floor, bare walls, and complicated ceiling.