The only safe route through a region of tetryon fields, where warp travel was found to be damaging subspace.
The Hekaras Corridor is a narrow passage through a region of space filled with tetryon fields, making it the only safe route through the sector. Heavy warp traffic along the corridor wears on subspace close to the Hekaran homeworld.
In Force of Nature, the Enterprise investigates the disappearance of the medical ship USS Fleming in the corridor. Hekaran scientists Serova and Rabal prove that warp fields are tearing subspace when Serova's sacrifice creates a rift. The Federation responds by limiting vessels to warp five except in emergencies.