One little thought that occurred to me in the shower and it has nothing to do with the technicalities of this new cache type more the implementation.
Basically, if you are going to publish a history cache, can you make a little effort to make sure the information you present is correct. As a history nerd I do sometimes check in on some of those "I remember....", "Lost.....", "Have you seen..." type historical Facebook groups. There is a lot of incorrect information being passed around as history. GCA caches do come up in Google searches (Google
the dip bridge mudgeeraba and you will see what I mean) and I think since we are essentially publishing information then I think we have a responsibility not to spread misinformation.
So please, if you are going to 'google' information for your own caches place more trust sites which might be published by local history societies or even council heritage departments. Most council libraries will either have a heritage or local studies branch or even just a shelf in their reference section for books on local places and events. The librarians are usually thrilled if you ask for help on this subject. Newspaper reports can be a little dodgy if they are being written in the modern era about an event long past so be wary. Having said that old newspapers can be invaluable. The National Library of Australia has many Australian newspapers available to search and read online through Trove
http://trove.nla.gov.au/?q=search. Trove is also an excellent resource for images/maps etc. PS It can be fun to search for an Australian ancestor in Trove, for example I knew my Grandmother was a card shark but I didn't know that she was skinning the local community in charity euchre tournaments in the district where she lived in the 1920s and 30s.
If you are going to include images, please acknowledge where you got them from and the photographer if known.
If you are going to put in information you 'know' but have not been able to verify elsewhere make it clear in your text "local legend says....", "When I grew up here it was believed....", or something like that.
I'm looking forward to both publishing and finding my first history caches.