Sutton Tunnel
... that two trains returning from the 1851 Chester races lost adhesion in Sutton Tunnel, and a third crashed into them, killing nine and injuring up to 40 people?
...  that two trains returning from the 1851 <a href="./Chester_Racecourse" id="mwDYs" rel="mw:WikiLink" title="Chester Racecourse">Chester races</a> lost adhesion in <b id="mwDYw"><a href="./Sutton_Tunnel_railway_accident" id="mwDY0" rel="mw:WikiLink" title="Sutton Tunnel railway accident">Sutton Tunnel</a></b>, and a third crashed into them, killing nine and injuring up to 40 people?