So after a few minutes on Google Maps using the satellite image function, I found that I had taken this as we flew over the German city of Cologne, on our way to London from Prague.
I am fairly sure now I snapped a few shots from the window as I always do on a plane, but will have taken this given it is place of note, and not just the countryside.
A quick search into Google for the BA route from Prague to London, a few minutes spent crawling along the route on the map and I found it. It's clearly Cologne given the shape of the river and the dark green area to the left.
I love the internet...! :)
3 good things:
1 - Nice flight from Prague to Heathrow
2 - Great run round the village after getting home
3 - Dinner with my folks