The Green Book: The Negro Travelers' Guide

I've written about The Green Book previously and it's always nice to revisit this bit of black history. If you haven't heard about this, there's a great podcast from 99% Invisible that talks about the Green Book and how it gathered data from African Americans all over the country through mailmen and functioned as a working travel guide for places that would be friendly to black people (in a time when it was legal to deny service based on the color of your skin).