ELR rail bridge sign for MCL/17. This sign says it belongs to London Underground, met line? Vine Street C17
<a href="//commons.wikimedia.org/wiki/User:Secretlondon" title="User:Secretlondon">Secretlondon</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>