I'm looking for either natural or human created letters and numbers. I hope at some point in the future to have a complete set of both upper and lower case characters.
Here are three to get started. Located at RAF Cosford, near Wallsall, West Midlands, England. ( 52°38'30.56"N, 2°18'52.60"W) Ultimately, though I want places with just one letter or number, and I want them to be big enough not to be pixellated when they fill a decent part of the screen.