If You Have 5 Days
Spend most of your first day at Guadalupe Mountains National Park in Texas. At McKittrick Canyon are three trails of varying lengths. On your first evening, view the bat flight at Carlsbad Caverns National Park and spend the night there.
On the morning of Day 2, return to Carlsbad Caverns to take the Natural Entrance Route into the depths of the cavern, after which you can loop through the interior, and then take the Big Room Route. That afternoon visit Living Desert Zoo and Gardens State Park in Carlsbad. In the evening consider strolling some of the scenic walkways along the Pecos River at the Lake Carlsbad Recreation Area.
On Day 3 drive north on U.S. 285 to Roswell, where you can stop at the Roswell Museum and Art Center and International UFO Museum and Research Center. Continue to Lincoln on U.S. 70/380 west and take in a bit of the Wild West before settling down for the night at one of the bed-and-breakfasts there. Spend Day 4 perusing the museums and galleries of Ruidoso and Ruidoso Downs. Spend the night at Inn of the Mountain Gods or at one of the many nice inns in Ruidoso. On Day 5, swing through Cloudcroft before examining the space ware at the New Mexico Museum of Space History in Alamogordo. Close your day and finish up the last roll of film at White Sands National Monument.