Tunnel under Zamkowy Square – tram and car tunnel of the W-Z Route in Warsaw, passing under Zamkowy Square. It was built 1948-1949. Thanks to it traffic between East and West Warsaw does not go through the Old Town and Zamkowy Square. In order to build t ruins of buildings of Krakowskie Przedmieście and Miodowa Streets were cleared out. Once the tunnel was built, the buildings were reconstructed on their original spots, and in the cellars of John Tenant House, on the Zamkowy Square, a hall of Warsaw’s first escalators was built – they connect the outlet of the tunnel level (with bus stops) with the Zamkowy Square.