Nestled in Texas' western tip, right on the border with NM, Guadalupe Mountains NP is not one of the more popular National Parks. Yet its still has a lot to offer, and is worth a couple days' visit.
Though a long drive from Tuscon, we arrived in late March and were able to find an available site in the later afternoon. Many of the tent only sites in the Pine Springs campground were walk-in, including ours, and far from the restrooms. Those were the downsides; the upsides were being surrounded by some pretty awesome mountains and a quiet atmosphere.
We spent our first full day in the park climbing Guadalupe Peak. At 8479 feet, its the highest peak in Texas, and from the trailhead (which is at the campsite), it is an 8.4 mile roundtrip with more than 3000 feet of elevation gain, and the park rates it as Strenuous. But after a similar hike in Death Valley to Wildrose Peak, we thought we were up for it and set out.
Neither the elevation nor the distance were any trouble, and we got to the top in only a few hours and had a quick break for some photos and a snack. The views from up top are excellent, though unfortunately it was hazy that day so we couldn't see as far as we would have liked. We could see over the top of El Capitan, a formation from a pre-historic reef that formed hundreds of millions of years ago when the area was covered by the sea. And, for a short while, we were the highest people in Texas. :)
When we got back to camp later that day, famished, Cristina had a stroke of genius and thought to make nachos on the campstove for dinner. Delicious.
The next day we hiked up to McKittrick Canyon to see what we were told was a lush canyon full of wildlife. There was water in the creek in places, but not so much on the wildlife. It was a short hike to Pratt Cabin and back nonetheless, with lots of striking scenery. We spent much of the rest of the day using the free wireless at the visitor center and catching up on a few things.
I get the sense that GMNP is a great place to do some good backpacking, though we didn't have that chance ourselves. There are several backcountry campgrounds, including one not far from Guadalupe peak, and we ran into lots of people on bc trips. The frontcountry is nice too, though, so this NP should definitely be on your lists!