bottomless ravine; abyss
Literary or figurative expression for an extremely deep, seemingly bottomless gorge. Often used metaphorically for a profound or dangerous situation.
He felt a despair like falling into a bottomless abyss.
深淵 is a more common and neutral word for 'abyss' or 'deep chasm', while 千尋の谷 is a set phrase with a classical, literary feel.
Standard kanji spelling using 尋, a traditional unit of depth.
Variant using 仭, an older or less common character for the same unit. Rarely seen in modern writing.
千尋 means 'a thousand fathoms' (尋 being a traditional unit of depth), and 谷 means 'valley' or 'ravine'. The phrase literally means 'a valley of a thousand fathoms', i.e., an immeasurably deep gorge.