ReversePP is a tool I developed to help with OSINT investigations in the UK by indexing planning application/permission data from local authorities nationally.

The link is to the search tool but you can learn more about the project at https://blog.reversepp.com/

The bit that is the most fun and perhaps of most interest here is that if you flick the "General Search Toggle" you can search applications by key word. A general search for "nuclear shelter" will take you to a planning application submitted to Bexley council in 1933 which apparently just confused them for 47 years.

Have fun and let me know what you think!