April 18 – The great 1906 San Francisco earthquake strikes, damaging the Southern Pacific Railroad's headquarters building and destroying the mansions of the now-deceased Big Four. Also destroyed are many cable car routes, which will be replaced with electric streetcars.
May 8 – A special train carrying E.H. Harriman makes a run from Oakland CA to New York in 761 hours and 27 minutes. This record will stand until October 1934, when it will be broken by Union Pacific Streamliner M-10000.
May 19 – The Simplon Tunnel between Italy and Switzerland, the world's longest tunnel until 1979, opens to rail traffic.
September 21 – A Grand Trunk Railwaypassenger train hits a stopped freight train at a crossover in Napanee, Ontario; the engineer stays at the controls trying to slow his train as much as possible and becomes the only fatality. The train's passengers later erect a monument in the engineer's honor.
^Wolmar, Christian (2005) [2004]. The Subterranean Railway: How the London Underground Was Built and How It Changed the City Forever. London: Atlantic Books. p. 181. ISBN1-84354-023-1.
Rivanna Chapter, National Railway Historical Society (2005). "This Month in Railroad History: July". National Historical Railroad Society. Archived from the original on September 30, 2007. Retrieved July 18, 2005.