Many travelers (readers of the Traveler excepted) mistakenly believe commercial facilities in the national parks – lodging, dining, and retail - are operated by the federal government. While national park officials have ultimate oversight on things such as pricing, these facilities are operated by private companies that bid for the right to rent rooms, operate dining facilities, sell T-shirts, and offer specified activities such as trail rides and guided tours. NPS rangers continue to staff visitor centers and offer interpretive activities, but nearly all commercial activities are handled by the private sector.