Attention-seeking postbox

I have no idea why Maltese postboxes are in the middle of the street instead on the side. 
I think this is a regular Maltese box, but there are several red postboxes remaining from British rule. We had that issue here but we painted ours green as soon as we could ;-) 
You can see how steep some streets are, and the Mediterreanean sea poking through in the background