Grid 310 was the Borg designation for a region of space in the Delta Quadrant located approximately thirty thousand light years from Earth.
In 2378, USS Voyager searched grid 310 for signs of the Friendship 1 probe. It was discovered that the probe had landed on an unidentified M-class planet located in this grid after Starfleet lost contact with it in that vicinity in 2248. (VOY: "Friendship One")