circle = | post office |
triangle = | discontinued post office |
square = | no post office |
[-- = | beginning of route |
--] = | end of route |
- - - - = | special delivery |
___m___ = | mail messenger |
+-+-+-+ = | rural delivery |
....... = | once per week |
- - - - = | twice per week |
_______ (brown) = | three times per week |
_______ (black) = | six times per week | |  |