The First Link is a useful Path for the First Mission, though a secondary version can be found on the other link that would follow along the future Rail Line that gets made down the other pass.

https://upload.wikimedia.org/wikipedia/commons/5/55/Chilkoot-trail.jpg

This next Link is a Historically Accurate Map of the Rail Line that gets made in the mission after sending wood to Bennet. The game does not allow for sharp Train Lines, so some corners will be Inaccurate in game, but for the most part, you can follow the path 100% of the way without Mods and with a 99% Accuracy to the Historical/Real Life version.

https://wpyr.com/excursions/wp-content/uploads/2021/07/WP-Summit-Excursion-Map-for-Web.jpg