Overview of Newtown Railroads
Selecting the Topo choice in Acme Mapper shows where the old railroad lines were by clearly indicating embankments.
Acme Mapper - Newtown (new window/tab)
Where the railroads intersected at the tunnel location, the curve of the lower level NY&NE becomes apparent.
The World Topo 4U is the clearest indicator of the current and orginal ROWs.
In addition, the "missing section" of embankment visible from Echo Valley Road (#3) is indicated on the map; as well as the reroute of the Housatonic as it approaches Newtown from the northwest (#4).
Bing Map's Bird’s Eye Views are leafless and show the curves of the old routes very well