Kolob Reservoir is a beautiful small reservoir on a mountain near Zion Park. It is managed as a blue ribbon fishery and usually offers good action for larger rainbow and cutthroat trout. It also offers some tiger and brook trout. Special regulations are in place to protect fish and allow them to grow large. Only two fish may be harvested and they cannot be between 15 and 22 inches. (All fish 15-22 inches long must be released.)
Bait fishing is allowed during the summer (third Saturday in May - second Saturday in Sept) but artificial flies and lures must be used during spring and fall.
There is a nice boat ramp at the reservoir. Boat motors must be 10 HP or less.
Camping is available by reservation only. The campground is nice and popular. See details here: https://www.hipcamp.com/en-US/discover/utah/kolob-campground
To reach Kolob Reservoir, from the town of Virgin drive NE on the Kolob Terrace Road. The road is paved but twisty and steep in spots as it climbs the mountain. You will go into and out of Zion Park a few times. The road leads right to the reservoir.
Winter access is by snowmobile only.