It's two small concrete pillars, with a bit of metal stuck on them.

Stu: Sorted out that huge image! ;-)

Looks small on  my screen now ??

There is definitely a face in the left hand one....

psychrn:

Stu: Sorted out that huge image! ;-)

 

Looks small on  my screen now ??

The yellow could be a marker for gas pipes??

Sorry can't help you but I wish I had one outside my place.

It's a GCSB listening post. Actually, two of them.

DarthKermit:

 

It's a GCSB listening post. Actually, two of them.

 

The left hand face definitely looks like a GCSB face....

Looks to be something written on the front of the two metal boxes, under about 20 layers of yellow paint. If you can read that it might give you a clue.

Or continue undoing the bolts on that box on the left - someone's already got most of that top left one off - and see what's inside! That's what I'd do, but my sense of curiosity sometimes make me do stupid things...

Old flux capacitor.

No longer fluxing.

Utilities are colour coded.  Yellow is usually gas.

1.  UFB external connection point c1945?

2.  Concealed switch to turn on water for fire brigade?  (Yellow for fire plugs)

3.  Connection point for some prehistoric telephone system?