north of the thames river, the modern-day wonderland road corridor consisted of: hutton sideroad, which existed from riverside drive 2.27 km north to the sarnia gravel road; a north-south 1.32 km section of sarnia road which ran from hutton road and then continued westwards along today's gainsborough road; north of this point, cameron sideroad continued northward (3.51 km within the post 1993 city limits) to highway 7. hutton sideroad passed under the canadian national railway tracks via a one-lane subway located slightly west of the current wider subway, which was constructed in the late 1950s. at some point in the 1970s, sarnia road was realigned to continue westward from hutton road along springhill road, and hutton road was extended northward along the former section of sarnia road and cameron road.