Unimatrix 424, Grid 03

From Memory Alpha, the free Star Trek reference

Unimatrix 424, Grid 03 was the Borg designation for a region of space.

In 2375, a Borg sphere, severely damaged in an ion storm and regenerating while traveling through this region at Warp 2, was intercepted by the USS Voyager, the crew of which mounted a successful theft of a transwarp coil. (VOY: "Dark Frontier")