This is Nevada?
The Bristlecone-Glacier trail is one of the most popular trails in Great Basin National Park. That being said, you still might not see more than a couple other people on this hike. Bristlecone pines are some of the oldest living things on earth, quite possibly the oldest living single standing trees in the world (there is some debate about aspen and other trees being older due to the interconnectedness of the root system, and the possibility that one stand of aspen may very well be one "individual"). There are trees that have been found in this Bristlecone grove that are approaching 5,000 years old. Unfortunately, the oldest known tree was also cut down in this grove before this area became Great Basin National Park.
Warning: The trailhead is at almost 10,000 feet, and you will be climbing at least 600 feet to the Bristlecones, 1100 if you plan to make it to the Glacier. Be prepared and know your limits. Remember the only cure for altitude sickness is to go to a lower elevation as soon as possible.
Start out from the trailhead at the end of the Wheeler Peak Scenic drive. Cross the bridge and turn right for the Bristlecone-Glacier, and Alpine Lakes trails. The trail ascends gradually through an Engelmann spruce forest. Before too long you will come to another junction for the Alpine Lakes Loop. Turn left to stay on track for the Bristlecones. The trail continues through some pretty forest, look around and you might be lucky enough to see and hear Clark's Nutcrackers flying through the trees.
At 0.7 miles you come to another trail junction for the Alpine Lakes Loop and Theresa Lake, continue left towards the Bristlecones. As you continue your ascent, the trail and the terrain around you gradually becomes more rocky. As you climb the spruce appear less frequently, and the trees are more spread out. You will now be seeing primarily Limber Pines and Bristlecone Pines from here on out. Keep an eye out on the left hand side for a little known lake, Brown Lake, a couple hundred yards off the trail. Brown Lake is the only lake in the park that is actually located in a Bristlecone grove and has many Bristlecones around it.
Continue hiking up the now rocky trail until you come to a sign marking the Bristlecone interpretive loop. This trail is very short, and definitely worth your time. Interpretive signs explain the scientific significance of the Bristlecones and how they are dated. They also have put signs under some of the trees that they have aged, the oldest one marked on the trail is 3200 years old, and it doesn't look like its going anywhere anytime soon. In season there may be a Park Ranger at the grove to answer questions and conduct guided walks along the loop trail.
After you complete the interpretive loop, follow the signs for the Glacier and turn left at the junction. Continue on into the Wheeler Peak cirque and soon you will find fantastic views of the peak, and depending on the time of year either snow fields or the Glacier itself. You will have to remind yourself that you are indeed in Nevada and not Colorado or Montana. This is one of the most beautiful areas in the park in my opinion. The trail will cross snow fields for all but a few weeks of the year, try your best to stay on the trail, as the alpine life is delicate. The trail ends at a sign that proclaims "Rock Glacier 10,800 feet". Enjoy the views of the peak, glacier, bristlecone grove, snake valley, and other parts of the snake range. This is a good place for lunch, but be advised early or late season hikers might find the cirque area cold and very windy.
When you are ready turn around and head back the way you came. Enjoy the rest of the park!
WARNING! Hiking and outdoor related sports can be dangerous. Be responsible and prepare for the trip. Study the area you are entering and plan accordingly. Dress for the current and unexpected weather changes. Take plenty of water. Never go alone. Make an itinerary with your plan(s), route(s), destination(s) and expected return time. Give your itinerary to trusted family and/or friends.