Instance of: http://www.w3.org/2004/02/skos/core#Concept
Subject Field Subject Field/48
Is Reference of Underground railway-en#Sense
Maanalainen rautatie-fi#Sense
U-Bahn-de#Sense
Untergrundbahn-de#Sense
Metropolitana-it#Sense
Chemin de fer souterrain-fr#Sense