Torre del Oro
...that the Torre del Oro, a watchtower constructed in the 13th century by the Almohad dynasty, protected the entrance to Seville's port with a large chain that stretched underwater from the tower's base across the river to stop unwanted ships?
...that the <b id="mwag"><a href="./Torre_del_Oro" id="mwaw" rel="mw:WikiLink" title="Torre del Oro">Torre del Oro</a></b>, a watchtower constructed in the 13th century by the <a class="mw-redirect" href="./Almohad_dynasty" id="mwbA" rel="mw:WikiLink" title="Almohad dynasty">Almohad dynasty</a>, protected the entrance to <a href="./Seville" id="mwbQ" rel="mw:WikiLink" title="Seville">Seville</a>'s port with a large chain that stretched underwater from the tower's base across the river to stop unwanted ships?