The user could select the subject (e.g. Boat builders, Fishing, Family name/tree, etc) with the relevant images then presented geographically on a map. Connections between related images (e.g. a family relative) could be shown as an arc between them.  A takeoff on this page <-- if you click on that link, then select the "Tour boatbuilders" checkbox, then dragging the map will bring up all the boat builders.  The filters (subject, date, surname, etc) would cause more or less items to be displayed on the map.
Filters, for
example...

Dates: ? 1990 1942
Locations: ? HT
Subjects: fish person uniform persons lighthouse
Surnames: Cash Malone Russell ?
Collaborators: WMHM