Fort Sill is an active military base and like most has some nice habitat. Some areas of the base have limited access, however. General access must be secured before entering. Under DoD guidelines, adults and certain children (children who are 16 years old or older and are driving a vehicle) without a current active duty military I.D. card, family I.D. or retiree I.D. must go through the Visitors Control Center for a pass card that will allow them unescorted access to Fort Sill.