Mountain range (4)
'mountain range' is the definition.
(Alps is an example)
This is all the clue.
(Other definitions for alps that I've seen before include "South-central European mountain system" , "European mountain range" , "Mountain system, highest peak Mont Blanc" , "Slopes" , "European mountains" .)
(Other definitions for ural that I've seen before include "Russian river giving name to mountain range" , "Russian river, rising in the mountains between Europe and Asia" , "2,400 km river flowing through Russia and Kazakhstan into the Caspian Sea" , "Runner" , "Russian river flowing into the Caspian Sea" .)
'mountain range' is the definition.
(a sierra is a chain of mountains)
This is all the clue.
(Other definitions for sierra that I've seen before include "Mountain range -- code word for S" , "Range of mountains with jagged peaks" , "A Spanish chain of mountains" , "Vehicle" , "Nato alphabet 'S'" .)