LOS ANGELES METRO HEAVY RAIL
Red Line and Purple Line

The Los Angeles Metro subway consists of two routes, both starting downtown at Union Station.  The lines split after five further stops outbound.  The shorter Purple Line heads only another two stations from that last joint platform, Wilshire/Vermont, out to a terminal at  Wilshire/Western.  The much longer Red Line goes generally northwest from the split into below-ground Hollywood, and then under the Hollywood Hills, ending up at North Hollywood in the San Fernando Valley.  The system's total length is about fifteen miles, all within the L.A. city limits.   

Of the fourteen heavy rail systems operating in eleven metropolitan areas of the country, only the LA Metro has its entire passenger route network underground.  Its running is efficient, but hardly fascinating. 

This view is at Union Station, with an empty car awaiting outbound passengers.