Switchbacks are for the weak
This hike is probably one of the hardest single hikes currently in the Grand Valley. The trail is very exposed, steep, and offers almost no shade in its ~2,000-foot climb to the top. Be prepared.
Mt. Garfield is one of the most prominent landmarks within the Grand Valley and offers a spectacular view of the surrounding countryside. This short but steep 1.4 mile (one way) trail takes you straight up the Bookcliffs and to the top!
Around 110-90 million years ago, western Colorado was covered by a shallow (~1,000 feet deep) sea, as part of the Western Interior Seaway. At its greatest extent, this seaway stretched from the Arctic Ocean to the Gulf of Mexico, and from Alabama to Utah. This seaway laid down several thousand feet of blackish shale, now called the Mancos Shale. This forms the bulk of the base of the Bookcliffs as well as the floor of the Grand Valley. While the seaway started retreating later in the Cretaceous, it left behind a series of shales and sandstones that now form what we call the Mesaverde Group. These shifting environments during the Cretaceous created swamps, some of which are preserved as coal beds and which have created interest in the rocks of the Mesaverde since Euro-American settlers first encountered them. There are several old mine remains along this hike, as well as unmined coal seams that can be seen underfoot and along the trail. The Utes have used this area extensively before the arrival of white settlers, and their petroglyphs can be seen by the sharp-eyed along the trail.
Be prepared. No, really. Be prepared. This trail is steeper than any Grand Canyon trail I've been on in the first mile. Plus the elevation change is similar to going from Indian Gardens to the rim. Don't be caught unaware.
The hike starts at the Mount Garfield Trailhead and heads straight up. There is a well-defined and obvious trail that leads up one of the Mancos ridges directly after cross the fenceline. The 3/4 mile is the steepest, with the trail rising at least 100 feet for every 1/10th mile. About 500 feet up the trail enters a boulder field and the trail becomes more indistinct. It is important to keep aiming up. Most trails reconverge as they near the rim. There are obvious ruins from a mining cable car (the headframe can be seen above the rim, at the next cliff up the slope); sticking to trails near these ruins will keep you on track.
Once you have reached the rim of the first meadow, the hardest part is over. There is a small meadow leading to a cliff set back from the first rim that the trail crosses. Although this section is short, it provides a nice reprieve from the grind that you've just passed. after a large boulder field on the west side of the trail, the uphill continues. As below, there are several possible trails to take. There is a visible notch in the ledge you are ascending, however, so as long as your track does not deviate too far from that, you are on the right track.
After this second ascent, you come to a second, larger meadow. Crossing this open area feels like a blessing, and the rise in the trail, as it leaves the meadow to side-hill the cliff, does not feel as daunting. The trail continues upward, rising towards the base of the sandstone cliff that dominates the northern portion of the trail. When you reach the base of the sandstone you also reach a pass and the last of the small canyons/meadows between you and the summit. You're only 0.48 miles from the summit but there's one more serious rise to overcome.
Crossing this last draw, the trail again splits as you search for the best way up. There is a trail on the right side of the rise, not always easy to see, that leads to almost the top of the sandstone ledges below the last plateau. Regardless, all the possible trails lead to roughly the same point - a narrow pinch-point just below the rim. Once you surmount this small (<5ft) rise, you're on the final plateau. The trail parallels the rim, splitting once or twice, but once the flagpole comes into view it is easy to find your way forward.
Once at the flagpole, take a well-deserved break. Look around, enjoy being above pretty much everyone else in the valley, or the view up to the Roan Cliffs above Rifle. When you are ready, return via the route you took up with extra care since many areas on the descent are slippery with rock debris.
None, bring all you need.
Theoretically possible, but I have never heard of it happening.
Hiking poles are highly recommended, especially for the descent portion of the trail.
Check out the Official Route and Triplog.
This is a moderately difficult hike.