Which Martian landform feature suggests sustained precipitation or runoff over geological timescales?

Answer

Dendritic valley networks

Dendritic valley networks, mapped by orbiters, are analogous to terrestrial river systems carved by erosion, strongly suggesting slow, sustained runoff or precipitation across ancient Martian terrain.

Which Martian landform feature suggests sustained precipitation or runoff over geological timescales?
MarsGeologywaterevidencehypothesis