The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- 600 V DC railway electrification (1 member)
- 76th Street (1 member)
- 78th Street (1 member)
- 79th Street (1 member)
- Abandoned Lines (1 member)
- Articles containing video clips (1 member)
- Blog posts (99 members)
- Browse (8 members)
- Candidates for deletion (0 members)
- DTA and MTA (1 member)
- Disambiguations (0 members)
- February 1963 (1 member)
- Forums (6 members)
- Ghost Tunnels (1 member)
- Help (3 members)
- Help desk (2 members)
- IND Second System (1 member)
- Images (0 members)
- Manhattan (1 member)
- Never Built Lines (1 member)
- New York City Subway (1 member)
- Pages by MatiK24 (1 member)
- Pages with broken file links (2 members)
- Pages with reference errors (3 members)
- Provisions by Mayor Hylan (1 member)
- Queens Tunnel (1 member)
- Railway lines opened in 1863 (1 member)
- Rapid transit in New York (state) (1 member)
- Roosevelt Island (1 member)
- Services and Transits (1 member)
- Standard gauge railways in the United States (1 member)
- Template documentation (28 members)
- Templates (29 members)
- Transit (1 member)
- Underground rapid transit in the United States (1 member)
- Watercooler (2 members)