Erect a pale in river in the dark (7)
I believe the answer is:
unaware
'in the dark' is the definition.
(I've seen this before)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for unaware that I've seen before include "Ignorant - unconscious" , "Without knowledge" , "Unexpected" , "Oblivious to, not knowing" , "Not having knowledge or realisation" .)