Vertical face to ascend on river (5)
I believe the answer is:
riser
'vertical face' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'ascend on river' is the wordplay.
'ascend' becomes 'rise' (rising is a kind of ascending).
'on' is a charade indicator (letters next to each other).
'river' becomes 'r' (abbreviation for river).
'rise'+'r'='RISER'
'to' is the link.
Can you help me to learn more?
(Other definitions for riser that I've seen before include "Vertical pipe in a building" , "Pipe for upward flow" , "upright portion of step" , "Vertical piece between two steps of stairs" , "Stair front" .)