This is the Atlin Classic. It is a well marked trail just 3.5km south of town along the Warm Bay Rd. It has beautiful views of Atlin Lake and the surroundings.
Time Required: 2-4hrs
Elevation Gain: 700m
A more detailed description can be found at: http://yukonhiking.ca/monarch.html
This trail is a remainder of the gold rush, at the end of the trail you will find the left overs of an old dam as well as several signs of hard labor as you hike up through the forest to the tree line.
This is an access trail to the alpine of the Johnson Range, which means you can tailor the hiking experience to the amount of time and fitness level of your party.
Time Required to treeline and back: 3-4hrs
Elevation Gain: 550m
How to get there: Drive south down Warm Bay Road for 16km. Here you will come to a bridge that crosses Mckee Creek. Park in the pull out on the other side. From here follow the small road and turn left at the fork. After 100m the road will be washed out and you will follow it and hold right for another 200m or so. Then on your right there will be a small quad trail going up that will turn a sharp left and go up a steep trail. From here just follow the trail to the tree line.