The easiest way to start the Rock Creek - Deep Creek hike is to park at the Deep Creek Campground next to the southern trailhead and hike as far up the trail as you like before heading back. Parking's free, though there's a fee to camp. There is also a vault toilet and potable water at the site. Some hikers prefer to start at the northern trailhead near the Arlington exit on I-80 (#272) and have a shuttle pick them up at Deep Creek Campground. Whatever way you do it, this rugged hike is a treat for the senses.
As you ascend from the Rock Creek trailhead, you'll follow the wide rocky creek to a majestic waterfall. You'll also cross many scenic bridges. In many places, the water has carved the rock into interesting shapes that are now carpeted in colorful moss and lichen. Tall pines tower over much of the trail. Enjoy the shade as you pass through the deep canyon. Water views abound: the trail starts near Sand Lake and passes by the smaller Crater Lake. Wildlife in the area include moose, elk, and bear, though they're often too shy to be spotted. Mountain lions also make the area home, so make sure to keep your dog leashed and close to you.
Berries grow in the forest and wildflowers abound in summer. Look for lupine and larkspur. The blooms continue into the open alpine meadows the trail winds through. Find your way back into the woods through stands of bright-barked aspen, and before you know it, you'll be emerging into another meadow. In one, soft grasses sway; in another, stiff scrubby sage resists the wind. Its characteristic green looks like it was dabbed on the landscape by a paintbrush after the happy little trees were complete.
In many places, slopes are nothing but stacks of flat rocks. These make for surprisingly steep scrambles. Channel your inner mountain goat to get past them and be careful. It's your choice whether you complete the entire length of the Rock Creek Trail or take a spur to see Crater Lake before heading back. You choose your own adventure here, but the day will always end with a wagging tail and a smile.