natural-depression

Narrow by natural-object 23 place 23 landform 22 valley 13 waterbody-bed 9 geological-formation 6 body-of-water 4 ocean-floor 4 cavity 3 natural-basin 3 ravine 3 canyon 2 gully 2 land 2 plain 2 crater 1 geological-trough 1 gorge 1 hollow 1 oceanic-trench 1 pelagic-zone 1 streambed 1 volcanic-crater 1