High Roller
... that High Roller was a roller coaster atop the Stratosphere Las Vegas, the tallest observation tower in the United States?
... that <b id="mwD5Y"><a href="./High_Roller_(Stratosphere)" id="mwD5c" rel="mw:WikiLink" title="High Roller (Stratosphere)">High Roller</a></b> was a <a href="./Roller_coaster" id="mwD5g" rel="mw:WikiLink" title="Roller coaster">roller coaster</a> atop the <a class="mw-redirect" href="./Stratosphere_Las_Vegas" id="mwD5k" rel="mw:WikiLink" title="Stratosphere Las Vegas">Stratosphere Las Vegas</a>, the <a class="mw-redirect" href="./List_of_tallest_freestanding_structures_in_the_world" id="mwD5o" rel="mw:WikiLink" title="List of tallest freestanding structures in the world">tallest observation tower in the United States</a>?