A
standard gauge railway has track with 4 foot 8½ inches (
1435mm) between rails. The
story of the standard gauge being derived from the
width of
Roman chariots is likely to be an
urban legend.
after
http://www.railpage.org.au/comrails/common/html/glossary_s.html
http://www.qnx.com/~glen/deadbeef/1897.html