
During the 1960s the US Government would launch the great societies program, which while primarily geared towards reducing poverty and other social welfare programs, also provided funding to construct new rapid transit lines across the country. The most famous of which would be in San Francisco (BART), Atlanta (MARTA) and Washington D.C. (WMATA).
These packs contain all the trains and liveries of each operator all in real colours.
The BART Pack:

The MARTA Pack:

The WMATA Pack:

You can find the set on BaNaNas, and the source attached to this post
Also, thanks to Leon on Discord for the banner on this post!