Compared to the weather in London today this photo has the complete opposite feel, but I re-found it browsing through some older photos. Liz and I had gone for a walk up through Blackheath to the top of Greenwich Park in the snow and as we reached the edge of the hill overlooking the rest of the park and London, I spotted this couple in an embrace and it was too good not to take a picture.
This was back when I had my Canon 5D Mark II and I happened to have the 24-105 f/4L (great all-round lens) on the camera so could zoom in and get the photo without disturbing the couple or missing the moment. With a little cropping to focus just on the couple and their surroundings it cuts out another couple of people on the left of the original frame that detract from the scene.
The squarer crop also works well with the tree acting as a frame around the right and top sides of the photo. The old Royal Naval College and Canary Wharf behind are also rarely an unwelcome backdrop; shot at f/4 and at 105mm there's also just enough compression to bring the background a bit closer while leaving it just distinct enough to recognise the landmarks without distracting from the main subject.