Activities do exist outside of drinking when you go to Las Vegas. I know it's crazy there are actually places in Vegas you don't have to be on the strip to have a good time (I know, bizarre, right?). Below is a list of great things for you and your friends to do that will get your heart racing, give your eyes a rest from bright neon lights and give your liver a break.
A word of caution though: a lot of the activities I'm recommending are a lot of fun but take place in a desert. Therefore, please take the necessary precautions such as bringing adequate water, sunscreen, and cold weather clothing (this is the desert. It gets super hot during the day and really cold at night).
With that disclaimer out of the way, let me show you the sites.
Visible from the Las Vegas Strip, Mt. Charleston is a local's favorite place to hike, camp, and RV. Mt. Charleston is part of the Spring Mountains, a range that runs from Southeast Nevada to the borders of California. The Mt. Charleston area has over a hundred and fifty camp sites and is accessible in some parts to RVs. If you find yourself in Las Vegas and looking for a place to get away from the hub-bub of the city, you'll find it here. If you happen to go in the winter, Mt. Charleston does offer some reasonable slopes for skiing and snowboarding. The next time you're in Las Vegas, give it a shot.
RED ROCKS CANYON
Partially in the Spring Mountains (where you'll find Mt. Charleston) Red Rocks is a great destination for great sightseeing. Named for its eponymous red rock formations, it also hosts a number of natural springs. These springs run along border of the Spring Mountains, so it may be possible for you to actually get to them from both sides.
One of the most iconic sites constructed during the New Deal is the Hoover Dam. Hoover Dam is a great spot to enjoy the sights constructed by man, but without the hub-bub of city life. The Hoover Dam is definitely a site to see as it's one of the largest concrete structures ever created. You can truly feel the spectacle of the sight, especially when you realize that people built this magnificent structure in the blistering heat of the Nevada desert two years ahead of schedule. It does cost a few bucks to take a tour, but trust me, it's worth it.
Lake Mead is a marvel, and is a creation of the aforementioned Hoover Dam. Around 24 miles southeast of Last Vegas, it is a perfect day trip site. If you have your own boat, canoe, or kayak, it can be a great activity for relaxation or refreshing workout. The hills and mountains in the area are also great places for ranging into the backcountry. The mountain ranges that surround Lake Mead provide perfect opportunities for scenic dates and bonding among friends. Just be aware that Lake Mead is a protected area of the National Park Service and does require a permit to take your boat on it. Certain places of Lake Mead (especially Black Canyon below) do require permits for whatever you decide to do. They're normally just a few bucks for everything besides boating, so if you have any questions give the National Park Service a call.
Once you're done exploring the Hoover Dam and Lake Mead, now's your chance for something faster. Black Canyon is a canyon on the Colorado River. There are a bunch of local companies that specialize in these services, and know all of the nooks and crannies. If you have your own canoe/kayak, or want to just go out and trailblaze you will need to purchase a permit from the National Park Service. It's only $17, which is completely worth it. Many of the kayak and canoe companies that will rent or take you on the Colorado River will also require you get to an NPS permit. But don't let that dissuade you. For a little bit of effort and a couple more bucks you'll have an experience you won't forget.
VALLEY OF FIRE
Valley of Fire is one of the oldest National Parks in the United States, and if you're planning on hitting the Lake Mead area, Valley of Fire should definitely be a part of it. Valley of Fire, like Red Rock Canyon, gets its amazing color and style from sandstone that's millions of years old. Amazingly, a place called Valley of Fire used to have local inhabitants: Native Americans. Some of their great art is still on display across the walls of the sandstone. If you're in the mood for exploring lands where ancient dwellers used to live and imagine how they lived in such scorching conditions, take a trip through Valley of Fire.