The Enterprise-D approaches the sphere. The huge size of this construction is emphasised by the fact that the ship is still many millions of kilometres away in this image. [1]
At closer range, all appearence of a spherical structure dissapears, and the Dyson sphere becomes an apparently flat wall. [1]
This entrance port has an entrance area some seventy times greater than the space doors of Starbase 74, the largest accessway in the Federation. [1]
The interior surface of the sphere was apparently designed to be class M across most of its area. [1]
The Enterprise-D escapes through the access doors. There are many hundreds of such ports on the sphere. [1]