

The 80-year-old concrete arrows that helped deliver the mail - hepha1979
http://www.theverge.com/2013/11/18/5116408/transcontinental-air-mail-arrows-helped-deliver-mail

======
ColinWright
Discussion:
[https://news.ycombinator.com/item?id=6453401](https://news.ycombinator.com/item?id=6453401)

