The National Park System is perhaps the federal land best known to the public. The National Park Service (NPS) in the Department of the Interior (DOI) manages 391 units, including units formally entitled national parks and a host of other designations. The system has more than 84 million acres. The NPS had an appropriation of about $2.39 billion for FY2008. For FY2009, the Administration requested $2.40 billion. FY2009 appropriations have not been enacted to date. The NPS estimates its level of employment at 20,739 FTEs for FY2008, and seeks funding for 21,649 FTEs for FY2009. The NPS statutory mission is multifaceted: to conserve, preserve, protect, and interpret the natural, cultural, and historic resources of the nation for the public, and to provide for their use and enjoyment by the public. The use and preservation of resources has appeared to some as contradictory and has resulted in management challenges. Attention centers on how to balance the recreational use of parklands with the preservation of park resources, and determine appropriate levels and sources of funding to maintain NPS facilities and to manage NPS programs. In general, activities that harvest or remove resources from units of the system are not allowed. The NPS also supports the preservation of natural and historic places and promotes recreation outside the system through grant and technical assistance programs. The establishment of several national parks preceded the 1916 creation of the National Park Service (NPS) as the park system management agency. Congress established the nation's first national park—Yellowstone National Park—in 1872. The park was created in the then-territories of Montana and Wyoming "for the benefit and enjoyment of the people," and placed "under the exclusive control of the Secretary of the Interior" (16 U.S.C. §§ 21-22). In the 1890s and early 1900s, Congress created several other national parks mostly from western public domain lands, including Sequoia, Yosemite, Mount Rainier, Crater Lake, and Glacier. In addition to the desire to preserve nature, there was interest in promoting tourism. Western railroads, often recipients of vast public land grants, were advocates of many of the early parks and built grand hotels in them to support their business. There also were efforts to protect the sites and structures of early Native American cultures and other special sites. The Antiquities Act of 1906 authorized the President to proclaim national monuments on federal lands that contain "historic landmarks, historic and prehistoric structures, and other objects of historic or scientific interest" (16 U.S.C. § 431). Most national monuments are managed by the NPS. (For more information, see CRS Report RS20902, National Monument Issues , by [author name scrubbed].) There was no system of national parks and monuments until 1916, when President Wilson signed a law creating the NPS to manage and protect the national parks and many of the monuments. That Organic Act provided that the NPS "shall promote and regulate the use of the Federal areas known as national parks, monuments, and reservations ... to conserve the scenery and the natural and historic objects and the wild life therein and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations" (16 U.S.C. § 1). President Franklin D. Roosevelt greatly expanded the system of parks in 1933 by transferring 63 national monuments and historic military sites from the USDA Forest Service and the War Department to the NPS. The 110 th Congress is considering legislation or conducting oversight on many NPS-related topics. Several major topics are covered in this report: proposals to enhance NPS funding before the agency's 2016 centennial; the NPS maintenance backlog; science-related activities at national park units; security of NPS units and lands; and management of wild and scenic rivers, which are administered by the NPS or another land management agency. While in some cases the topics covered are relevant to other federal lands and agencies, this report does not comprehensively cover topics primarily affecting other lands/agencies. For background on federal land management generally, see CRS Report R40225, Federal Land Management Agencies: Background on Land and Resources Management, coordinated by [author name scrubbed]. Overview information on numerous natural resource issues, focused on resource use and protection, is provided in CRS Report RL33806, Natural Resources Policy: Management, Institutions, and Issues , by [author name scrubbed], [author name scrubbed], and [author name scrubbed]. Information on appropriations for the NPS is included in CRS Report RL34461, Interior, Environment, and Related Agencies: FY2009 Appropriations , by [author name scrubbed] et al. Information on BLM and Forest Service lands is contained in CRS Report RL33792, Federal Lands Managed by the Bureau of Land Management (BLM) and the Forest Service (FS): Issues for the 110 th Congress , by [author name scrubbed] et al. Several other NPS-related topics are covered in other CRS reports. For example, how national park units are created and what qualities make an area eligible to be an NPS unit are of continuing interest. (For more information, see CRS Report RS20158, National Park System: Establishing New Units , by [author name scrubbed].) Legislation has been considered in recent Congresses to study, designate, and fund particular National Heritage Areas (NHAs) as well as to establish a process and criteria for designating and managing NHAs. (For more information, see CRS Report RL33462, Heritage Areas: Background, Proposals, and Current Issues , by [author name scrubbed] and [author name scrubbed].) Recent decades have witnessed increased demand for a variety of recreational opportunities on federal lands and waters. New forms of motorized recreation have gained in popularity, and the use of motorized off-highway vehicles (OHVs) has been particularly contentious. (For more information, see CRS Report RL33525, Recreation on Federal Lands , by Kori Calvert et al.) (by [author name scrubbed]) To be ready for the NPS's 100 th anniversary in 2016, the Administration and Congress have proposed multi-year initiatives to strengthen visitor services and other park programs. The National Park Centennial Initiative, first announced by President Bush in August 2006, seeks to add up to $3 billion in new funds for the parks over 10 years through a joint public/private effort. The initiative has three components: (1) a commitment to add $100.0 million annually in discretionary funds; (2) a challenge for the public to donate at least $100.0 million annually; and (3) a commitment to match the public donations with federal funds of up to $100.0 million annually. In furtherance of the first component of the initiative, for FY2009 the Administration requested additional funds within the line item "Operation of the National Park System." Specifically, the Administration is seeking a total of $2.13 billion in park operations for FY2009, an increase of $160.9 million over the FY2008 level of $1.97 billion. FY2009 appropriations for NPS programs have not been enacted to date. The Administration also had sought, and received, an increase in park operations for FY2008, the first year of the centennial initiative. For the third component of the initiative, the President proposed establishing a mandatory program with $100.0 million annually for 10 years to match private donations. Companion legislation ( H.R. 2959 and S. 1253 ) has been introduced to create a mandatory program along the lines of the President's initiative. The bills would establish the National Park Centennial Challenge Fund in the Treasury consisting of cash donations and matching appropriations from the general fund of the Treasury. The match may not exceed $100.0 million for each of 10 years beginning with FY2008. The funds are available, without further appropriation, to finance "signature projects and programs." These projects and programs will be identified by the NPS Director as helping prepare the national parks for another century of conservation, preservation, and enjoyment. Another House bill ( H.R. 3094 ) also would establish a National Park Centennial Fund in the Treasury, but would take a different approach. It would consist of $30.0 million annually over 10 years. The funds would be available beginning with FY2009, and would be available without further appropriation. The Administration is to include a list of proposals for funding in its annual budget submissions to Congress. The proposals must be consistent with certain criteria and initiatives set out in the bill. The bill specifies seven park initiatives, in the areas of education, diversity, support for park professionals, environmental leadership, natural resource protection, cultural resource protection, and health and fitness. No matching funds would be required, but the Secretary of the Interior may accept donations for centennial projects and programs. The bill also provides a $30.0 million "offset for the Centennial Fund by repealing Section 9 of the Land and Water Conservation Fund Act." That provision of law currently provides $30.0 million of annual contract authority for federal land acquisitions. In its cost estimate on the bill, the Congressional Budget Office estimates that "this provision would have no effect on direct spending because that contract authority is not presently used by the NPS, and CBO does not expect that it will be over the 2009-2018 period." A central issue of debate has been how to finance the Centennial Fund. Under H.R. 3094 as introduced, the Centennial Fund was to consist of $100.0 million annually, with the funds derived from fees for commercial activities on DOI lands.