- The Inland Trunkline, NH's predecessor railroad New York & New England's mainline, runs from Poughkeepsie to Woonsocket. It would here link to Providence via RRI's Blackstone Valley Line and Boston via the MBTA's Franklin Line*.
- The Along the Shore Line, the former New Haven mainline and current Northeast Corridor mainline, runs from New York to Westerly en route to Boston**.
- The Housatonic Valley Line runs from New York, diverging from Along the Shore at Norwalk, crossing the Inland Trunk at Danbury, and on up the eponymous river valley between the Taconics and Berkshires to North Canaan en route to Pittsfield and North Adams***.
- The Naugatuck Valley Line runs from New Haven to Winsted via Bridgeport, Waterbury, and and the Housatonic's tributary, the Naugatuck. Alone of all of these lines, it does not have any connection at its northern end^.
- The (Lower) Connecticut Valley Line runs from New Haven to Springfield via Hartford. It is a core service already offered by Amtrak and funded by CT DOT. Key scheduling improvements center around ensuring hourly clockface and excellent connections.
- The Quinebaug Valley Line is named for the Thames River tributary it follows for most of its length. Located in relatively rural eastern Connecticut, it runs from New London to Worcester^^.
Prospector model (top), Class 222 (above) the Stadler GTW (below), Siemens Desiro (bottom), or some other example (like Bombardier's Talent).
As New England is a collection of small states whose regional-level rail would need to be unified, Connecticut regional rail can be expected to be no more than a part of the overall system. To see the whole, then, requires understanding this project's connections to Rhode Island and Massachusetts systems.
*At Woonsocket, it would connect to Rail Rhode Island's Blackstone Valley Line; it would also connect to an extension of the MBTA's Franklin Line to its natural terminus (i.e. Woonsocket). The section between Putnam and Blackstone would supersede RRI's Putnam Branch, which brings the alignment up the Woonasquatucket back into play--especially if the alignment can be reclaimed to Webster.
**The New Haven Line and Shore Line East currently inhabit this alignment. In fact, Shore Line East offers part of a convenient operations nucleus to build the network around, even if (as commuter services) it would be turned over to MNRR. Along the Shore would also need the least resources of any of these lines, principally filling in Northeast Regional service gaps (if any) and ensuring an MNRR-RRI connection at Westerly.
***From North Canaan to North Adams is Massachusetts' purview. North Canaan itself is a pretty poor terminus. The line itself would duplicate MNRR commuter/regional service to New Milford (extended from the current terminus at Danbury).
^This line duplicates MNRR from Bridgeport to Waterbury.
^^Incidentally, this also allows me to cut RRI's own Thames Valley Line back from Norwich to Plainfield.