For one thing, thre are basically two different types of caves, true caves with winding passages (almost always confined to limestone) and rockshelters, basically shallow overhangs, often in sandstone.<br><br>The deep passages in these caves are not suitable for fires, although the mouth of such a cave might have a rockshelter. A fire in a deep passage would do considerable damage to the cave resources, plus there is not likely to be much fuel.<br><br>Rockshelters are a different thing. They make absolutely wonderful campsites and shelters. With a fire, they can be absolutely luxurious - far better than any tent. This is one reason that many of them, especially the ones best suited for shelter, were used in the past and are now archeological sites.<br><br>The result is that you will often see existing smoke blackening on the ceiling. Fire scarring on the walls of the rockshelter is less common and is often the result of a prehistoric oonflagration.<br><br>To prevent more damage, keep your fire small and away from the wall, or better yet, use a stove. This also allows you to slip into the space between the fire and the wall where you will be kept warm by both the direct heat of the fire and the reflectance off the shelter wall. <br><br>Avoid damage to the archeology which is often present. Build your fire in clean soil/sand and don't disturb the contents of the shelter. Your fire will burn fine and you will be shielded from rain and snow in the typical desert rockshelter. <br><br>One of the best camps I ever made was in a huge rockshelter in the Four Corners, just north of Navajo Mountain. We camped to the side of archeological material on sterile ground, awakening in the morning to rain and a rising creek which barred further travel. We made pancakes and retired to our sleeping bags, where I finished my Tony Hillerman novel - talk about an appropriate setting! About noon, the creek dropped, and we proceeded on our way. We were totally comfortable, completely dry, the entire time.