Las Vegas isn't just the strip. Red Rock Canyon is just beautiful. Absolutely beautiful. As the sun moves across the sky the mountains change colors and it is gorgeous. There are over a dozen different trails/hikes you can go on from beginning level to advanced. If you like to rock climb you will love Red Rock Canyon. There are maps showing the different trails and the levels of difficulty available from the BLM. If you have a gun and like to target practice there is also a target shooting range.
If you don't have a car you can take a Lyft or Uber out there as well as one of the many tour companies like Pink Jeep Tours.