Just took a quick look at mine, I have 57 G in my "Mining" folder, this is subdivided into "General Mining" and "Mining Photographs", the latter is 27G.
Both are sorted into sub directories named after main districts, eg "Derbyshire", "Nenthead" etc. So not necessarily counties, but area that basically suit me. Then more sub directories each being a particular site. Dates, camera settings etc can be seen in a photos property sheet, obviously digital cameras only. Stuff from old film cameras need more thought.
My system is set up to suit me not Mr Gates, dont use the Windows installed folders, "Documents" etc, but my own directory structure, "Shared Documents", "Shared Data Files" etc in the root. This is because my system is a Local Network, probably what a lot of folk would call an "Office System", multiple machines hard wired as an Ethernet on the 169.254 block.
To satisfy anyone's curiosity, the "Shared data Files" is the MS Outlook shared pst file, the back end data to LEL Lamps, and back end data to other stuff such as Mining Journal index etc.
I described my system in detail in some other thread. Cant remember where.
Backup is to other machines storage and also removable media.
My avatar is a poor likeness.