If you are interested in this, here is my idea for an inner-city Denver Streetcar system to be built after this suburban system being built now is complete. I actually show it in phases. Dark blue is phase 1. Light Blue is phase 2. Pink is phase 3. Green is what will be built with FasTracks.
I have Civic Center Station serving as the Streetcar Hub. Phase one is all about rebuilding Civic Center Station into a new hub station with the capacity to handle my plan, and connecting it directly with Union Station. I have this Civic center-Union Station line as a possible subway line (as it will be very high capacity, with multiple converging streetcar lines all sharing it. It would stub end below grade in front of Union Station and the escalators would come up directly into the historic Union Station.
After this infrastructure is put in place, the streetcar lines can start growing out from Civic Center Station, in a series of phases.
Now on the Northwest side of Union Station, I have the streetcar lines coming in from the north, right into the Light Rail Terminal proposed for Union Station. Since I am proposing modern streetcars, which are actually just single car light rail vehicles, they would actually be compatible with existing light rail tracks, stations and maintenance facilities. So from Highlands, the streetcar line would travel down Platte Street, cross over the river at 20th Street and come in along the CML into an extended LRT Terminal at Union Station.
Here is the plan, check it out!
And here is how I propose the subway portion of this proposal (~1 mile subway portion) from Civic center Station to Denver Union Station be integrated into Denver Union Station. The pedestrian access to and from the subway platforms would go directly into the Historic Union Station building! As seen on the left side, coming up into the station building (the right side the the Union Station plan being built now for other lines underway).