#tunnel  a passageway through or under something, usually underground (especially one for trains or cars); "the tunnel reduced congestion at that intersection"
  supertype:  passageway  a passage between rooms or between buildings
  subtype:  catacomb  an underground tunnel with recesses where bodies were buried (as in ancient Rome)
  subtype:  railroad_tunnel  a tunnel through which the railroad track runs
     subtype:  chunnel__Channel_Tunnel  the railroad tunnel between France and England under the English Channel
  subtype:  underpass__underpas  an underground tunnel or passage enabling pedestrians to cross a road or railway

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