itch.io Spring Selects Series A
On Sale: GamesAssetsToolsTabletopComics
Indie game storeFree gamesFun gamesHorror games
Game developmentAssetsComics
SalesBundles
Jobs
Tags

Looks like I was wrong, it appears that advance warning indicators for speed restriction segments were only introduced after 1971 and just in some places; acknowledging of the speed restricted areas is being left to the driver, either through learning the track or through time table documents (if there were any).