Scotsman's following motor route to reach mountains (11)

'mountains' is the definition.
(the Carpathian Mountains is a mountain range)

'scotsman's following motor route' is the wordplay.
'scotsman's' becomes 'ian's' (common Scottish name).
'following' is a charade indicator (letters next to each other).
'motor' becomes 'car' (informal term for car).
'route' becomes 'path' (synonyms).
'car'+'path'='carpath'
'ians' put after 'carpath' is 'CARPATHIANS'.

'to reach' is the link.