This page is dedicated to cities with unfinished, abandoned, or "secret" metros.

Abandonded System
Abandonded Stations
Secret Subway

Algiers
Baghdad
Belgrade
Boston
Campinas (not underground)
Cape Town
Charleroi
Cincinatti
Donetsk
Fort Worth
Glasgow
Harbin
Jacksonville, FL
Johannesburg
Katowice
Krakow
Lagos
Laurel, PA
Lebedyan, Russia
Liege
Liverpool
London
Los Angeles
Melbourne
Moscow, RU
Omsk
New York
Newark
Paris
Philadelphia
Rochester
Rostov-na-Donu
Sarajevo
Scranton
Seville
Sydney
Toronto
Vancouver
Vienna
Ufa

Mention is also made of the secret Palestine branch of the DART light rail. In Lebedyan, Russia, a secret subway is allegedly being dug by hand.