The IND system as we know it today is only about two thirds what was planned as far back as 1929. Here are a number of pages that deal with the scope of the unbuilt lines, some scans of original tracing prints, and the BAHN INDNOT layout.
| IND Second System Introduction |
| South Fourth St Subway |
| Utica Ave Subway |
| IND Second System Service |
| IND Prospect Park Line to Staten Island |
| IND Not Built Requires BAHN 3.81 or later |
- The JoeKorNer