We joined a mountain biking excursion with REI Adventures. The trip took place near Scottsdale, Arizona in the Sonoran Desert. There were seven participants and two guides. REI provided full suspension mountain bikes, tents, camping gear, and all the meals. We just had to show up and ride. The desert in the late fall is beautiful and not too hot. We had a little rain but not enough to spoil the riding the next day. The group rode different routes every day starting from our base camp in the McDowell Mountain Regional Park. One of the days we piled into the REI van and drove to Brown's Ranch Trailhead for an exhilarating day navigating around boulders and cactus on pristine trails with just enough rocks and gravel to make it interesting. Each day, the terrain was mostly non-technical single track with plenty of climbing, turns, and descents to make it a very fun riding experience.