The Enterprise under attack in the Bandor system
The Bandor system was a remote area of space which in or shortly before 2370 fell into Federation jurisdiction.
The system had at least one planet with many moons and asteroids, or smaller planets close by. The nearest Federation outpost to the system was Starbase 122, which it would take two days for a class-9 probe to deliver information to from the system.
In 2370 the USS Enterprise-D was sent to map the system where it was attacked by an unknown assailant. (TNG comic: Strategy)