Betula birch cascade current flow green habitat moss natural nature norway norwegian pour pure quality rivulet rock stone stream trees water woodland Fluvial landforms of streams Forrest landscape Mountain River Natural landscape outside hiking Riparian zone vegetation watercourse waterfall waterway achieve America boulder cascades enjoy peak relax rest sit sitting sky snow success summit three top Trek trekker trio usa walker World azure blue croatia dams lake lakes landcape mountains national park Plitvice protected area rocks stones summer bronze figurine fountain gig god gods leister mighty myth neptune omnipotent power powerful protect protection roman mythology sea spear statue symbol trident watch