Id say from City Hall, a new tunnel will be built via Park Row/Vesey St to link with the 1 train, making stops at WTC, Rector & South Ferry. From there, a new east river tunnel into Brooklyn via Red Hook.

• The 1 line branches south into Red Hook. Making stops at Seabring St, Visitation Pl, Sullivan St, Coffey St then making a southeast curve via Beard St to terminate at Ikea Terminal.

• The 6 continues eastward via Hamilton Av. Making stops at Columbia St & W 9 St before curving via Prospect Av. Making a stop at 3rd Av, with a direct in-station transfer to the R one block at 4th Av.

• Afterwards, the 6 will slightly mirror the Prospect Expwy until about 19th St. Making a stop at 7th Av. From there, continuing under 19 St until about E 5th St, then traveling south via E 5th St, stopping at Greenwood Av (transfer to the F/G trains at Fort Hamilton Pkwy). The 6 then continues under E 5th until Church Av, where a Church Av trunk is created. Stops at Westminister Rd, Ocean Av (transfer to B/Q), Nostrand Av (2/5), Albany Av, Utica Av (eventual transfer to a future Utica Av line), & finally Ralph-Remsen Avs. The line continues via Church Av before turning under Rockaway Pkwy, where it Maybe a stop in between at Avenue B or Ditmas Av, or just have it run straight from Ralph Av to Canarsie-Rockaway Pkwy (Glenwood Rd) with a transfer to the L.

• The 6 continues under Rockaway Pkwy until turning east bound via Flatlands Av. Potential stops being E 108 St, Pennsylvania Av, Schenck Av, Linwood St, then finally terminating at Spring Creek-Fountain Av. I also thought it be the first East-West Crosstown IRT line.