I remember some of my favourite spaces in the city I lived in where narrow valleys between buildings like this. The trick for light (enough for a great garden) was to hang cheap mirrors on the top part of each side wall.
If i remember correctly most had a deal along the lines of they will maintain the wall exterior (paint, looking for damage ect.) as the tall building really did not have easy access to their outter wall.
I remember some of my favourite spaces in the city I lived in where narrow valleys between buildings like this. The trick for light (enough for a great garden) was to hang cheap mirrors on the top part of each side wall.
I was thinking whitewash and mirrors! If the owners of the buildings either side even allowed it that is.
If i remember correctly most had a deal along the lines of they will maintain the wall exterior (paint, looking for damage ect.) as the tall building really did not have easy access to their outter wall.