The Montgomery Canal has a long straight section, just south of the Perry aqueduct. It then heads towards Rednal Basin. It wasn’t always this way though.
When the canal was originally under construction one of the members of the original Ellesmere Canal Committee persuaded the company to divert the course of the canal to run closer to his estate (the Woodhouse estate), with a short branch towards his house. Later the canal was moved back to its original planned line. As with so many things about the canal, the original documents are either vague or missing. Apprently the now disused section continued to hold water for some time though, and was marked on old maps as “old Canal”. I can’t find any of these maps though!
So, the Google Earth overlay below is based on what I can see, and make a best guess based on ground markings, lines of trees, and a sketch of the the old line. I can’t see the branch to the house though. If you know more, you can always email me.
Information from “Montgomeryshire Canal and the Llanymynech Branch of the Ellesmere Canal” by John Horsley Denton (1982).