hard shoulder 
noun British
A hardened strip alongside a motorway for stopping on in an emergency.Using the emergency telephone on the hard shoulder of the motorway gives a fixed location unlike a mobile phone....
- In other areas of the M1 earmarked for a new carriageway, additional land would be bought, with the hard shoulder and central reservation staying the same.
- In one short conversation, Pc Lee Bowdell described how Mr Hinde was flailing about on the motorway hard shoulder and deliberately banging his head on the floor.