There are two footbridges across St Davids station in Exeter. This one, at the north end, was originally only used by railway staff for parcels barrows and so could only be accessed by lifts. When these were replaced with passenger-operated ones this staircase was built (matching the ironwork of the other bridge) in case the lifts failed and people had to be evacuated from the bridge. It takes them down to platforms 3 and 4 in the middle of the station.
<a href="//commons.wikimedia.org/wiki/User:Geof_Sheppard" title="User:Geof Sheppard">Geof Sheppard</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>