The History of the Olympic Pictograms: How Designers Hurdled the Language Barrier.
Tag: pictographs
Icons, pictograms, and pictographs from The Noun Project
Motorway Logo
National Park Service Pictograms and Symobls
NPS symbols are free and in the public domain and contain all sorts of symbols and pictograms (or pictographs if you like), including recreation pictographs, north arrows, bar scales, road shields, accessibility, winter recreation, and water recreation. One of my favorites is the dam pictogram above.
Download them in Illustrator, PDF, TrueType Font Symbols and map patterns here: Map Symbols & Patterns for NPS Maps.