Cottonwood Spring is an oasis in the lower corner of Joshua Tree National Park, where the high Mojave desert gives way to the hotter Colorado Desert, and a small cluster of fan palms and cottonwood trees grows around a spring that has been used for centuries. The Cahuilla people gathered here, grinding seeds and mesquite beans in rock mortars, and the holes can still be seen in the boulders. Later, gold miners camped by the water, and ruins of their mills survive in the hills.
The spring itself is a modest affair, but in a landscape this dry, a patch of shade and a trickle of water are very valuable. Birds come in, from migrating warblers to roadrunners, and bighorn sheep sometimes drink in the early morning. The surroundings are low, open desert of creosote bush, ocotillo and cholla, and in good years in spring, wildflowers cover the ground in yellow, purple and white. A short trail leads to Mastodon Peak, a rocky hill with views over the valley and the old mine workings.
The ride south from the main part of the park is a long, gentle descent, from the stands of Joshua trees through a sloping desert of boulders and into a wide, sandy basin, with the Pinto Basin on one side and the Eagle Mountains rising on the other. The road is smooth, quiet and flowing, with long straights, and it takes you from one ecosystem to another, with the temperature climbing as you drop. At the end, you reach the interstate, and the sudden rush of traffic feels harsh after the silence.
Mecca, to the south, has more services. Summer heat is severe, so ride early, wear light gear and carry plenty of water. The best months are from late October to April, and the night sky is magnificent.