The first real stop of the trip, and the point where Southern Ontario ends and the Canadian Shield takes over for the next day and a half.
Sudbury Junction station sits about 10 km outside the city of Sudbury itself, at the end of a dirt access road off LaSalle Boulevard East — it is not downtown Sudbury and there's nothing within walking distance. If you're picturing a city-centre platform where you can see anything of Sudbury, that's not this stop; it exists purely as a rail junction point.
The scheduled stop here runs roughly 20–30 minutes, mainly for a crew change and to let passengers off the platform for air. It's not long enough to leave the immediate station area, and the train crew does not delay departure for a wandering passenger — stay within sight of the platform.
Depending on the season and time of day, this stop can happen in daylight or after dark — the westbound Canadian typically passes through in the evening of its first day. If it's daylight, the transition from farmland to the exposed granite and black-spruce forest of the Shield is already visible in the approach; if it's dark, this is effectively the last thing you'll see clearly until morning.
Cell service is patchy from Sudbury Junction onward and drops out almost completely for long stretches through the Shield overnight. If you need to make a call or send a message that can't wait, this stop and the platform area are a more reliable place to do it than relying on signal further west before Winnipeg.