Atatürk Dam
...the world's longest tunnel system is the two parallel tunnels at the Atatürk Dam of Şanlıurfa in southeastern Turkey?
...the world's longest <a href="./Tunnel" id="mwDiY" rel="mw:WikiLink" title="Tunnel">tunnel</a> system is the two parallel tunnels at the <b id="mwDic"><a href="./Atatürk_Dam" id="mwDig" rel="mw:WikiLink" title="Atatürk Dam">Atatürk Dam</a></b> of <a class="mw-redirect" href="./Şanlıurfa" id="mwDik" rel="mw:WikiLink" title="Şanlıurfa">Şanlıurfa</a> in <a class="mw-redirect" href="./Southeastern_Anatolia_Region,_Turkey" id="mwDio" rel="mw:WikiLink" title="Southeastern Anatolia Region, Turkey">southeastern Turkey</a>?