English: Composited digital illustration depicting the West portal of the CPRR's "Summit Tunnel" (Tunnel #6) which was in continuous use by the CPRR, SPRR, and UPRR from 1868 to 1993 at Donner Pass (Norden, California) on Track #1 of the original "Sierra Grade" of the Central Pacific Railroad. (The tracks removed in 1993 have been digitally restored in this illustration.)
日付
原典
(Original text: The Cooper Collection of US Railroad History (private collection))
{{BotMoveToCommons|en.wikipedia|year={{subst:CURRENTYEAR}}|month={{subst:CURRENTMONTHNAME}}|day={{subst:CURRENTDAY}}}} {{Information |Description={{en|Composited digital illustration depicting the West portal of the CPRR's "Summit Tunnel" (Tunnel #6) whi