The lower sections of the Starbase are occupied by various manufacturing
plants, including industrial replicator factories, for the construction
of starships.
The Enterprise-D arrives at Starbase 74. The design is externally almost
identical to the Spacedock-type station, including the huge internal
bay.
The huge size of these stations is emphasised by the fact that the
doors visible in this image are nearly two thirds of a kilometre across.