The mission to Starbase 174 was listed on a chart
Starbase 174 was a 24th century Federation starbase. The starbase was located in the region between Sectors 21166 to 23079.
In 2367, the USS Hood underwent a major system upgrade at Starbase 174. (TNG: "Brothers" production art)
The assignment of the Hood was not mentioned on screen, but rather was seen on a starship mission status chart during Star Trek: The Next Generation's run, beginning in TNG Season 3.