The Phase II IND subway system included the much anticipated Second Ave line as well as some lesser known lines that were never built. The Second Ave Subway actually had some construction done. The other mainline, the South 4th Street Subway, had only a hint of construction, where it would have connected or intesected with the IND lines that were built.
The main part of this line was to connect with the stub end tracks at 2nd Ave-Houston on the F train, a dead end connection via Worth St from just north of the C/E terminal at WTC, and a tunnel from the 2nd Ave line also around Houston St. This would have been a total of three tunnels with six tracks connecting Manhattan with the northern part of Brooklyn.
The roof of the East Broadway station of the F train has room for the Worth St line to cross it.
There were at least two separate plans for the connections to the east of the current Crosstown line. There a massive six track-four platform station (much like Hoyt-Schermerhorn) was built into the roof of the Broadway station. This was to be the main transfer point for converging trains. The Hope Tunnel web site has photos of the station shell at Broadway on the Crosstown Line.
This had a two level maze of connecting tracks between Havemeyer St and Varet St along South 4th, Beaver and Bushwick. One pair of tracks would have turned under Myrtle Ave, while the other two pair would have been a four track line under Stuyvesant Place feeding into Utica Ave.
In the roof of the Utica Ave Station of the A train at the (railroad) south end you can see the structure of the unused Utica Ave subway.
In addition, the middle track of the Bedford-Nostrand Station of the Crosstown line would have continued on Laffayette to Stanhope St, where it turn slightly to the north to meet the line on Myrtle Ave, also forming a four track line.
This was much more complex and if built, would have presented some interesting services. The same six tracks would have met at Havemeyer St. Two more would have ended at a third level of the Broadway Station of the Crosstown. These eight tracks would have split again into:
4 tracks on Flushing Ave to Horace Harding Blvd.
4 tracks along Broadway Brooklyn
4 tracks along Utica Ave.
The 1929 schemeatic of the IND had a number of other interesting lines:
Six track 2nd Ave line north of 61st St
Concourse Line Extended via 205th St to Baychester Ave and Boston Road
2nd Ave line taking over the White Plasins and Pelham lines of the IRT
NO 63rd St Tunnel, but a 61st St line from 6th to 2nd Ave northbound
Extension of Liberty Ave Subway to Springfield Blvd
Connection from 78th St on the Jamaica line via Fresh Pond Rd, Central Ave and the LIRR to Rockaways
An extension to the IRT Flatbush line to Utica and Voorhees (along with the IND line from Utica)
- The JoeKorNer
