After Donald Trump announced his plan to build a massive wall on the US-Mexican Border the world went wild. But history has shown that walls can be useful. These are 5 walls that worked!\r<br>\r<br>SUBSCRIBE to Top Lists: \r<br>\r<br>10 Craziest Political Candidates - \r<br>\r<br>Like us on Facebook: \r<br>\r<br>Follow us on Twitter:
