The first rail connection close to Edmonton came in 1891 the planned Calgary and Edmonton Railway choose to build its terminus south of the North Saskatchewan River, in what soon became the rival settlement of Strathcona.
In 1903, the Canadian Northern Railway opened a short spur across the Low Level Bridge, linking Edmonton with Strathcona, but Edmonton's major introduction to the rail age came in 1905 when the CNoR's main transcontinental line reached it from Winnipeg. The CNoR's station was located at what is now 104 Avenue and 101 Street, and its yard to the west. Around this yard, Edmonton's warehouse district developed.
Over the years the the downtown railyard created a barrier to other traffic and the Rat Hole and 105 St Overpass were built to get vehicles across the tracks. In 1928, a new station was opened at 101 Street and 104 Avenue, and was expanded in 1948. In 1964, it was demolished to make way for Edmonton's first skyscraper, the CN Tower.The yards functioned until 1988, and the last freight sheds were demolished in 1996.
Today MacEwan Unversity campus, Oliver Square shopping, and the Downtown Arena are all located on the former rail yards.
Portions from Wikipedia: http://en.wikipedia.org/wiki/Old_Canadian_National_rail_yard