Hello,
I created an icon package which contains symbols from the US National Park Service. There are over 250 symbols in 16 categories available in two packages - one normal and one inverted (dark).
A picture showing some of the symbols and additional information (description, source material) can be found on my website:
https://www.dfgtec.com/map-nps-symbols.html (https://www.dfgtec.com/map-nps-symbols.html)
Second (inverted) set - would not fit with first post.