O'Hara's Tower
... that O'Hara's Tower was built in the mistaken belief that it would enable the garrison at Gibraltar to spy on ships massing at Cadiz?
... that <b id="mwDm0"><a href="./O'Hara's_Tower" id="mwDm4" rel="mw:WikiLink" title="O'Hara's Tower">O'Hara's Tower</a></b> was built in the mistaken belief that it would enable the garrison at <a href="./Gibraltar" id="mwDm8" rel="mw:WikiLink" title="Gibraltar">Gibraltar</a> to spy on <a href="./Spanish_Navy" id="mwDnA" rel="mw:WikiLink" title="Spanish Navy">ships</a> massing at <a class="mw-redirect" href="./Cadiz" id="mwDnE" rel="mw:WikiLink" title="Cadiz">Cadiz</a>?