Thorn injury, with cries heard in part of the UK (5,5)

'part of the uk' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'thorn injury with cries heard' is the wordplay.
'injury' is an anagram indicator.
'with' is a charade indicator (letters next to each other).
'cries' becomes 'wails' (wailing is a kind of crying).
'heard' shows a homophone (sound like).
'wails' is a homophone of 'wales'.
'thorn' with letters rearranged gives 'north'.
'north'+'wales'='NORTH WALES'

'in' is the link.

Can you help me to learn more?