Climbers flock to Joshua Tree from around the world to tackle the literally thousands of routes open to them. There are challenges for all ability levels, with more than 8,000 climbing routes, 2,000 boulder problems and hundreds of natural gaps to choose from. Because Joshua Tree has its own particular set of safety issues, from high temperatures to remote climbing spots, it pays to do your homework first. If you're unfamiliar with the park, you'll want to purchase a climbing guide and hiking map, which are available at park visitor centers and online.

Certified guides can also lead you on climbs and provide a great way to explore in safety. If you do hire a climbing guide, make sure that they are permitted to work in Joshua Tree National Park. Each guide is required to have rock guiding certifications through the Professional Climbing Guides Institute, the American Mountain Guides Association or similar organizations. They are also required to be certified in Wilderness First Aid and CPR and must carry insurance.

With some of the darkest nights in Southern California, Joshua Tree National Park offers visitors the chance to see the stars, planets, meteors and even the Milky Way without much in the way of light pollution. On clear nights, you should have no problem viewing the stars from anywhere in the park. That said, surrounding communities do impact Joshua Tree's night skies, so the farther you are from them, the better you'll be able to see.

Visitors can park at any of the roadside pullouts and set up chairs to stargaze. The Pinto Basin Road between the Cholla Cactus Garden and Cottonwood has the least traffic and darkest skies, according to the National Park Service. Rangers regularly offer programs about the night sky. Check online or at any visitor center for details.

The main visitor center to the park houses a bookstore, cafe and restrooms. It's a good place to start your visit, pick up maps and find out what might be happening in the park that day. Rangers run public programs on a variety of topics and can offer advice on hikes and sightseeing.

Recent visitors said the center is a great place to pick up souvenirs, get advice from rangers and use the clean facilities.

This viewpoint is not to be missed as it offers a sweeping overview of the Coachella Valley from an elevation of 5,185 feet. A 0.2-mile loop trail leads up to the ridge, where you'll be able to look for sights including the Salton Sea, which is 230 feet below sea level; the Santa Rosa Mountains and the 10,800-foot San Jacinto Peak behind Palm Springs; and the San Andreas Fault, which runs 700 miles from the Gulf of California to the Mendocino Coast north of San Francisco. According to recent visitors, the views are awe-inspiring.

Keys View is located 20 minutes by car from Park Boulevard down Keys View Road. Access to the lookout is free. You can learn more about Keys View by visiting the NPS website.

The Cholla Cactus Garden, located about 12 miles south of the park's North Entrance, is home to one of the few stands of cholla cactus in the park. The short, quarter-mile Cholla Cactus Garden Nature Trail is a flat loop, which takes visitors to see the plants, of which the "teddy bear cholla" is the main attraction.

Identifying the teddy bear cholla is easy. It has densely interlaced yellow spines, tightly clustered stems and a dark lower trunk. Another name for this cactus is "jumping cholla," because the stem-joints, which have tiny barbs on the spines, easily latch on to anything near it. Make sure to stay a healthy distance away, as the barbs are painful to remove, according to recent visitors, who say look, but don't touch the fuzzy-looking cactus.

This is a short and sweet 1-mile loop trail located east of the Ryan Campgrounds. The hike takes visitors along an old ranch road to see remains of a historic adobe buildings from the 1800s. Once a large property, comprised of a main house, a bunkhouse and another building, the compound was built by J.D. Ryan, who operated a nearby mine.

Recent visitors described the hike as easy and found the remains of the homestead quite poignant.

Cottonwood Spring Oasis, located 7 miles from the park's South Entrance, served as an important place both for Cahuilla Indian Tribe and gold miners who depended upon its water. Today, visitors can see remnants of a primitive type of gold mill, as well as concrete ruins of two later gold mills.

There are several hikes in and around the area, including an easy hike to a second oasis and a short hike to the remains of a mill. A 3-mile loop trail to Mastodon Peak features great views and leads to the Mastodon Mine and the Winona Mill Site. Meanwhile, the longer Lost Palms Oasis trail is an 8-mile trek that rewards hikers with the largest stand of fan palms in the park. Cottonwood also shelters a campground, located about a half-mile from the spring.

This short trail is an easy 0.4-mile loop which takes visitors through Joshua tree woodlands and between unique rock formations. The trail is located at the junction of Park Boulevard and Keys View Road. Look for adaptive species that thrive in microhabitats, such as shady boulder crevices. Interpretive signs describe the types of deserts shrubs and other plants that live here. Desert sage, Mojave yucca, silver cholla and New Mexico thistle are just some the plants you might spot.

Recent visitors appreciated how close to the road the trail is and enjoyed the easy walk. Many were also impressed by the rock formations.

A popular stop along the drive through the park is Skull Rock, which as its name suggests, resembles a human skull. According to the National Park Service, the granite rock face was formed by water erosion over the centuries.

Recent visitors said it's easy to climb the rock and take a quick photo, but that there isn't much else to do here. Skull Rock is located along Park Boulevard. Parking spots are located just across the road from the rock. Visit the NPS website for more information about this unusual landmark.