It’s another one of those Embankment phone boxes!

(Coordinates 51°50’70.9″N, 0°12’19.7″W.)
I used to marvel at the amount of red phone boxes on the Embankment when watching the London Marathon on TV and seeing the elite athletes bomb past them at a rate of one every ten seconds. I did not pass one every ten seconds at my pace, but there were still quite a lot!
Another Embankment phone box next week.