key terrain
Military and geographic term for terrain that, if controlled, gives a marked advantage.
This hill is regarded as key terrain from a strategic standpoint.
要地 is a more general term for an important place or strategic point, while 緊要地形 specifically refers to terrain features critical in military operations.
Compound of 緊要 (urgent/important) and 地形 (terrain). The exact historical derivation is uncertain; the term is used in modern military contexts.