When viewed from the Earth this crater appears oval in shape due to foreshortening, but it is actually relatively circular.

The smaller crater Cysatus intrudes into the eastern rim of Gruemberger.

This crater has undergone steady erosion from minor impacts, so that the features along the rim and inner wall have become softened and rounded.

Significant impacts nearby have covered the floor and sides with ejecta, and there are a multitude of tiny craterlets along the inner wall.

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Gruemberger.