There are many Christian camps in the U.S. Some estimates on the number of Christian camps exceed 3,000 and the oldest of these organizations have been in existence for more than 100 years. The greatest concentrations of Christian camps are in the states of Pennsylvania, California, Texas, and Michigan. With the widespread popularity of Christian camps over so many years, one might ask, "What's a Christian camp all about?" That can be a difficult question to answer. Even camps that identify themselves as Christian can vary widely in their teachings and practices. However, a basic definition of a Christian camp is a temporary community that uses the outdoor setting, activities, and trained leaders to reach spiritual objectives. Some Christian camps are program camps, meaning they provide a program and campers come to the camp independently. An example of this type of Christian camp is Camp Kaskitowa near Allegan, Michigan. Other Christian camps are rental camps, meaning they rent out their facilities and typically provide staff and meals to the groups that rent them. The groups then provide their own programs. An example of this type of Christian camp is Brookhaven Retreat near Hawkins, Texas. Brookhaven Retreat also rents its facilities and provides staff, meals, activities, etc. to retreat groups in the non-summer months.