Dug up in Passau — near the Danube (9)
I believe the answer is:
unearthed
'dug up' is the definition.
(I've seen this before)
'in passau near the danube' is the wordplay.
'in' indicates a hidden word.
'UNEARTHED' is hidden within 'passau near the danube'.
(Other definitions for unearthed that I've seen before include "Excavated, brought to light" , "found" , "Dug up" , "Discovered something hidden by digging" , "unsafe condition of electrical apparatus" .)