DDOT posted this 1942 map by Capital Transit to help people navigate around the city by bus or streetcar:
Fares were 10¢ or 50¢ for six. You could buy a monthly pass for $1.25. And unlike today, you could transfer for free between bus and rail.
One block of text urges “housewives” to “help Washington’s War Effort” by only “travel in business shopping areas only between” 10 am and 3 pm. That’s because 300,000 people were getting to and from work outside those times.
The streetcar numbering also shows where we get today’s bus line numbers (for routes that don’t have a letter). Many of the lines followed routes very similar to major bus corridors today.
The 30 followed Wisconsin Avenue NW and Pennsylvania Avenue SE, and today, that’s the 30 series buses. The 40 and 42 lines followed Connecticut and Columbia to Mount Pleasant, as the 42 (and 43) buses do today. The 50s lines used 14th Street, the 70s Georgia Avenue, 80s Rhode Island Avenue, and the 90s a rough circle around the central city, like their modern equivalents.
The 60 took 11th Street and ended at the north end of Columbia Heights. This matches the commercial district there today, but the modern 62 and 63 mostly use Sherman Avenue through this area and continue farther north.
The 20 route no longer exists; it followed the Potomac River to Glen Echo.
And finally, the 10 streetcar line went to Rosslyn and (with the 12) H Street and Benning Road. The eastern part of this became the X lines (X is the Roman numeral for 10).
If you’re wondering whether historical streetcar precedent suggests whether the streetcar should go up Georgia Avenue to Silver Spring or to Takoma, the map is no help; the 72 cut east to Takoma while the 70 stayed on Georgia (though it ended just before the District line).
Finally, the Mall (or, at least, West and East Potomac Park) had a sort of Circulator: the Hains Point line, but only on Sundays in the summer.