<a href="https://en.wikipedia.org/wiki/Tower_Subway" id="mwhw" rel="mw:WikiLink" title="Tower Subway">Tower Subway</a>, the world's first <a href="https://en.wikipedia.org/wiki/Rapid_transit" id="mwiA" rel="mw:WikiLink" title="Rapid transit">underground tube railway</a>, opens in London, England, United Kingdom.