The hill is on the Canadian National Railway's Waukesha Subdivision, which used to be operated by the Soo Line Railroad.
The Wisconsin Central Railroad first operated over this hill until 1961 when it was merged into the Soo.
In 1987, the Soo launched the Lake States Transportation Division to sell off its least profitable lines.
Byron Hill is noteworthy in that helper engines are sometimes still used to assist trains making it over the grade.
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