Not a particularly impressive picture in my opinion but I like the contrast between the relatively bright ground and the very dark sky at Montjuic, Barcelona. The dark clouds led to a thunderstorm about half an hour after the picture was taken.

Bonus pictures:

The first picture is the sunrise over a cold, misty Dublin from high in the sky:

This one is my favourite one, which is also the same sunrise but over Wicklow a bit later: