Engaña Tunnel
... that the Engaña Tunnel was once the longest railway tunnel in Spain, but was never used?
... that the <b id="mwDgA"><a href="./Engaña_Tunnel" id="mwDgE" rel="mw:WikiLink" title="Engaña Tunnel">Engaña Tunnel</a></b> <i id="mwDgI">(pictured)</i> was once the longest <a href="./Rail_transport" id="mwDgM" rel="mw:WikiLink" title="Rail transport">railway</a> <a href="./Tunnel" id="mwDgQ" rel="mw:WikiLink" title="Tunnel">tunnel</a> in Spain, but was never used?