#rugged terrain

• Hollow-filled — Featuring many hollows, structural irregularities, or pronounced cavities; a terrain, path, or physical environment full of deep pits, valleys, or successive depressions. In a stylistic or regional sense, the term describes a geomorphologically fragmented surface that hinders movement and naturally collects runoff water.
• Hollowed — Characterized by many depressions, relief irregularities, or pronounced cavities; a terrain, landform, or waterbed featuring a succession of deep hollows or ravines. In a structural sense, it describes a rugged surface that drops abruptly into depth, being the opposite of a smooth or flat area.
• Arduous — Executed or taking place with great difficulty, requiring sustained efforts, patience, time, and energy; characterized by structural obstacles or hardships that are difficult to surmount. Referring to roads, terrains, or routes, the term describes a rugged configuration that is difficult to traverse and tiring for travelers.
• Anfractuous — Presenting deep irregularities, sinuous cavities, deep cracks, or twisting turns; characterized by a rugged and difficult-to-access surface. In a topographic sense, it describes a rocky relief full of narrow valleys and precipices, while in anatomy, it refers to an organic structure provided with deep convolutions or irregular grooves, such as the cerebral cortex.
• Sudden rush — An extremely rare lexical regionalism found in ancient dialects, used to describe a violent action, a powerful blow, a sudden rush, or an unexpected collapse into a hollow or steep slope; the term can also refer to a wild stretch of land, a rugged, steep place, or a hidden ground rupture. Its semantics are closely tied to the idea of uncontrolled dynamics, tumbling, or wandering through difficult terrains.