This article lists anniversary events related to rail transport that occurred on December 20.

• 1865 – Alkmaar railway station in the Netherlands is opened.

• 1909 – Henry Fowler is appointed Chief Mechanical Engineer of the Midland Railway, succeeding Richard Deeley.
• 1914 – Tokyo Station in Japan opens.
• 1925 – Ise Railway (Iseden) opens the Iseden Kambe Line connecting Ise-Wakamatsu Station to Ise-Kambe Station in Japan.
• 1969 – The Tokyo Metro Chiyoda Line is opened between Kita-Senju and Ōtemachi stations.
• 1979 – The Tokyo Metro Chiyoda Line branch to Kita-Ayase station is opened.
• 1992 – Western Australian Premier Dr. Carmen Lawrence presides over official opening ceremonies for Warwick railway station on the Transperth Joondalup Line.

• 1858 – David Blyth Hanna, first president of Canadian National Railway, is born (d. 1938).

• 1889 – William Stroudley, locomotive and carriage superintendent for Highland Railway 1865-1870; locomotive superintendent at London, Brighton and South Coast Railway's Brighton Works 1870-1889, dies {b. 1833).
• 1893 – George C. Magoun, Chairman of the Board of Directors for Atchison, Topeka and Santa Fe Railway in the late 1880s, dies (b. 1840).