The National Trails System Act of 1968 (NTSA) established the Appalachian and Pacific Crest National Scenic Trails,¹ and authorized a national system of trails to provide outdoor recreational opportunities and to promote access to the nation's outdoor areas and historic resources. Since the act's passage, the system has grown to encompass trails in every U.S. state, the District of Columbia, and Puerto Rico.

The system includes four types of trails:²

• National Scenic Trails (NSTs) display significant characteristics of the nation's "physiographic regions," representing desert, marsh, grassland, mountain, canyon, river, forest, or other areas. NSTs are extended trails that provide for outdoor recreation and for the conservation and enjoyment of significant scenic, historic, natural, or cultural qualities.
• National Historic Trails (NHTs)³ identify and protect travel routes of national historic significance, along with associated remnants and artifacts, for public use and enjoyment. NHTs can include land or water segments,⁴ marked highways paralleling the route, and sites that together form a chain or network along the historic route.
• National Recreation Trails (NRTs) are on federal, state, or private lands that are in, or reasonably accessible to, urban areas. They provide for a variety of outdoor recreation uses.
• Connecting or Side Trails provide public access to the other types of nationally designated trails or connections between such trails.

Congress plays an ongoing role in shaping the National Trails System through legislation and oversight. Congress establishes new trails within the system; directs the Administration to study potential new trails; determines the level of agency funding for trail management; and considers whether new trail categories (such as "national discovery trails") should be included in the system, among other roles. For individual trails, Congress has made specific provisions concerning land acquisition, trail use, and other matters. Ongoing issues for Congress include whether to designate additional trails, how to balance trail designation with other potential land uses, whether trail designation should be accompanied by federal land acquisition, what activities should be permitted on trails, and how to appropriately balance federal and nonfederal funding for trails, among other issues.

Background

During the early history of the United States, trails served as routes for commerce and migration. Since at least the early 20^th century, trails also have been constructed to provide access to scenic areas. The first interstate recreational trail, now known as the Appalachian National Scenic Trail, was developed in the 1920s and 1930s.⁵ In 1945, legislation to establish a "national system of foot trails" was introduced but not enacted.⁶ In the years following the Second World War, the nation sought increased opportunities to enjoy the outdoors.⁷ In 1965, in a message to Congress on "Natural Beauty," President Lyndon Johnson called for the nation "to copy the great Appalachian Trail in all parts of our country, and make full use of rights-of-way and other public paths."⁸ Three years later, the National Trails System Act was enacted.

The system began in 1968 with two scenic trails: the Appalachian National Scenic Trail, which stretches roughly 2,200 miles from Mount Katahdin, ME, to Springer Mountain, GA;⁹ and the Pacific Crest National Scenic Trail, which covers roughly 2,650 miles along the mountains of Washington, Oregon, and California.¹⁰ The system was expanded a decade later when Congress designated four historic trails with more than 9,000 miles and another scenic trail along the Continental Divide with 3,100 miles.¹¹ Currently, there are a combined 32 NHTs and NSTs covering roughly 58,300 miles (see Table 1 and Figure 1.)¹² Additionally, the system contains more than 1,300 NRTs located in every state, the District of Columbia, and Puerto Rico, as well as seven connecting or side trails.¹³ The National Trails System Act also authorizes the preservation of abandoned railroad rights-of-way for rails-to-trails conversions (16 U.S.C. §1247).¹⁴

Figure 1. Map of National Scenic and National Historic Trails

Source: CRS with centerline data adapted from National Park Service, "National Trails System Interactive Map," at https://nps.maps.arcgis.com/home/index.html. GIS data for Chilkoot NHT and Butterfield Overland NHT provided to CRS by NPS. Notes: Trail colors are for purposes of distinguishing the trails and do not indicate categories.

Designation Process and Requirements

Pursuant to NTSA, NSTs and NHTs are designated by acts of Congress.¹⁵ Prior to establishing a trail, Congress typically directs the Secretary of the Interior or the Secretary of Agriculture to study the route for potential inclusion in the system.¹⁶ The studies address both the suitability (i.e., characteristics that make the proposed trail "worthy of designation as a national scenic or national historic trail" ¹⁷) and the feasibility (i.e., physical and financial viability) of adding the trail to the system. Generally, NTSA specifies that both NSTs and NHTs are intended to be "extended trails," meaning trails or trail segments that total at least 100 miles in length; however, the law specifies that historic trails need not meet this minimum length.¹⁸ The act contains additional specific criteria for NHTs, which must (1) be established by historic use and be significant because of that use; (2) be significant with respect to a broad facet of American history, such as trade and commerce, exploration, migration and settlement, or military campaigns; and (3) have significant potential for public recreational use or historical interest.¹⁹

In contrast to national scenic and historic trails, national recreation trails and connecting and side trails may be designated by the Secretaries of the Interior and Agriculture with the consent of the federal agency, state, or political subdivision with jurisdiction over the lands involved.²⁰ Recreation trails must be existing trails that are reasonably accessible to urban areas and must meet other criteria as prescribed by the act or by the Secretaries.²¹ In general, the FS—acting through the authority of the Secretary of Agriculture—is responsible for designating NRTs on land administered by the Department of Agriculture (national forests, national grasslands, certain national recreation areas, etc.) and associated lands.²² The Secretary of the Interior is the designating official for NRTs located on all other federal lands and those located on state, local, and private lands. The Secretary of the Interior has delegated responsibility for administering the NRT program to NPS.²³

Figure 2. National Recreation Trails Designated by Year: 1969-2022 (as of September 2022)

Source: CRS, using information provided by NPS, Office of Legislative and Congressional Affairs, and from American Trails, National Recreation Trail Database. Notes: The first national recreation trail (NRT) was designated in 1969. There was an increase in NRT designations in the late 1970s under the Carter Administration due, in part, to a directive to federal land management agencies to designate trails under their jurisdiction. Specifically, in 1978, the FS was directed to establish 145 additional NRTs by January 1980, with a goal of two NRTs in each National Forest System unit. A minimum goal of 75 new NRTs was also established for public lands administered by agencies other than the FS. See U.S. Congress, House, "Message from the President of the United States, A Review of His Administration's Programs for the Protection of the Environment," 96th Cong., 1st sess., August 2, 1979, 96-174 (Washington: GPO, 1979), pp. 24-25.

Trail Development

The NTSA specifies that NSTs are to be extended trails (at least 100 miles in length) and that they are generally intended—though not required—to be continuous routes.²⁴ In practice, most NSTs are not "complete" or fully developed prior to or upon designation by Congress; however, the route is often designated as a continuous trail in establishing laws. The designation of a new NST by Congress thus serves as an authorization to the administering agency to establish a continuous trail for public use.

Similar to NSTs, the exact route and development of NHTs are typically not finalized at the time of designation. The NTSA requires NHTs to be designated as continuous routes, but unlike NSTs, the law specifies that the developed trail need not be continuous.²⁵ NHTs are typically corridors composed of historic sites and segments linked via marked tour routes that follow the original trail as closely as possible.

Following designation by Congress, the NTSA directs the Secretary to "select the rights-of-way" (generally considered to be the trail corridor) for NSTs and NHTs.²⁶ The corridor must be selected with the advice and assistance of landowners, land managers, and other applicable parties. Once the trail corridor is established, the process of developing NSTs and NHTs begins. Development of the trail occurs in accordance with the statutorily required comprehensive management plan for the trail in question. Such plans are to be completed within two years following designation and include protection and development plans for trail segments, potential cooperative agreements with nonfederal partners, and anticipated costs for land acquisition. The trail development process is generally an ongoing, years-long effort that involves planning, coordination among stakeholders, land acquisition, and other activities (for more information on land acquisition activities, see "Land Acquisition Authority"). In general, the federal government works with nonfederal entities who own land on which the trail corridor passes to obtain the necessary rights-of-way (in this case, typically meaning a legal right or privilege to use the land for one or more purposes) so as to allow recreation and use by the general public.

By contrast to NSTs and NHTs, NRTs and connecting and side trails are generally existing trails that are continuous and in use at the time of designation. As a result, the Secretaries generally need not establish rights-of-way for these trails, as any necessary ones typically are established prior to designation.

Land Acquisition Authority

For each of the four trail types in the system, routes may intersect both federal and nonfederal lands. For example, the roughly 60,000 miles of NSTs and NHTs often traverse a patchwork of federal, state, and private lands. This makes the completion or development of NSTs and NHTs following designation challenging. Agencies take a variety of approaches in establishing the necessary legal rights-of-way and ensuring access to a trail as intended by the NTSA. One such approach is direct acquisition of land or interests in lands. Section 7 of the NTSA establishes some general authorities for federal land acquisition for the purposes of managing and protecting national trails.

Along the designated corridor for NSTs and NHTs, the Secretaries may acquire land in that is within the boundaries of areas that are already under their administrative jurisdiction (e.g., on trail segments that lie within the boundaries of an existing national park or national forest but are not federally owned). Outside their administrative boundaries, the Secretaries are to encourage state and local governments either to acquire trail lands or to enter into agreements with private landowners for the necessary rights-of-way. Only if state and local governments fail to do so may the federal government acquire the land or form cooperative agreements with private landowners directly.²⁷ The law states that when federal acquisition is necessary, the federal agency may acquire land by donation; by purchase with donated or appropriated funds; by exchange; and, in certain limited situations, by condemnation.²⁸

When adding individual trails to the system, Congress has often included specific provisions limiting the full use of NTSA's land acquisition authorities. For example, Congress included a provision explicitly prohibiting the use of federal funding for land acquisition for certain trails in the late 1970s and early 1980s.²⁹ In 2009, P.L. 111-11 removed this prohibition but limited land acquisition for these trails—as well as multiple other existing and newly established trails—to instances involving a willing seller. At other times, Congress has limited acquisition authorities by establishing a geographical boundary for land acquisition, such as within a quarter-mile on either side of the trail.³⁰ As of December 2022, the federal land agencies have access to all NTSA land acquisition authorities for six of the 32 NSTs and NHTs.³¹

For NRTs, the provisions are more limited, in that federal land acquisition may take place only within an agency's existing administrative boundaries.³² Agencies are permitted to acquire lands or interests in lands through cooperative agreements, donation, land exchange, or by purchase with donated or appropriated funds. Connecting and side trails may include nonfederal lands only if no federal acquisition is involved (e.g., by obtaining an easement or right-of-way).³³

Organization and Management

Either the Secretary of the Interior or the Secretary of Agriculture, acting through the land management agencies, administers the 32 national scenic and historic trails. The NPS administers 21 of the 32 trails; the FS administers 6 trails; the Bureau of Land Management (BLM) administers 1 trail; and the NPS and BLM jointly administer 2 trails.³⁴ The administering agency typically develops the trail management plan,³⁵ oversees the development of trail segments, coordinates trail marking and mapping, develops maintenance standards, coordinates trail interpretation,³⁶ administers cooperative and interagency agreements, and provides financial assistance to federal and nonfederal entities for trail purposes, among other functions.³⁷ For most NSTs and NHTs administered by NPS, a full-time trail administrator (or superintendent) operates out of a field office located on or near the trail in question. For trails administered by FS and BLM, the agency may assign a full-time administrator or may rely on regional office staff (or in the case of BLM, state office staff).

The agencies distinguish between trail administration and trail management: while there is usually only one administering agency, multiple federal agencies, state and local governments, private groups, and individuals may own and manage the lands a national scenic or historic trail traverses.³⁸ NTSA authorizes the administering Secretary to enter into cooperative agreements with state or local governments, landowners, private organizations, or individuals for trail development, operation, and maintenance.³⁹ In addition, several federal agencies involved with the trails signed a memorandum of understanding (MOU) to coordinate federal trail management.⁴⁰

Trail administrators and trail managers also regularly coordinate work with a variety of nonfederal trail partners, such as charitable foundations, volunteer groups, and advocacy organizations. These trail partners help to plan and maintain the trails, develop outreach programs, and connect with the public. Some NSTs and NHTs have established formal relationships with a single organization that operates across the length of the trail and serves as an "umbrella" coordinator for local partners.⁴¹ Others work with a series of partners that vary depending on their mission or the geographic area in question.⁴²

In contrast to the NSTs and NHTs, NRTs are typically administered by states, localities, and private organizations since they are primarily located on nonfederal lands. When NRTs do cross federal lands, the applicable federal agency is responsible for administering the trail. NPS is responsible for the overall coordination of the NRT program, which includes overseeing the nomination and designation process for new trails both on and off federal land.⁴³ Nonfederal trail managers for NRTs have access to federal training and technical assistance, and are eligible for some types of federal funding.⁴⁴

Connecting or side trails are administered by the Secretary under whose jurisdiction the trail lands are located.⁴⁵ Currently, the Secretary of the Interior administers all seven existing connecting or side trails.⁴⁶

Trail Uses and Protections

The types of uses and activities permitted on national trails—as well as the degree to which designation confers federal protections over such areas—vary depending on the type of trail, the jurisdictions traversed by the trail, and any voluntary agreements in place between the administrating agency and relevant landowners. In addition, Congress may include provisions in establishing laws that either prohibit or allow certain uses or activities on specific trails.

For NSTs and NHTs, NTSA generally authorizes the Secretary to permit uses that "will not substantially interfere with the nature and purposes of the trail."⁴⁷ Such uses may include, but are not limited to, bicycling, cross-country skiing, day hiking, equestrian activities, jogging or similar fitness activities, overnight and long-distance backpacking, snowmobiling, and surface water and underwater activities.⁴⁸ The use of motorized vehicles by the general public is typically prohibited on national scenic trails.⁴⁹ However, motorized vehicles may be allowed on national historic trails if they do not substantially interfere with the nature and purposes of the trail and were allowed by administrative regulations at the time of designation.⁵⁰ NTSA also authorizes the Secretary of the Interior and the Secretary of Agriculture, in consultation with relevant agencies and parties, to issue regulations "governing the use, protection, management, development, and administration of trails."⁵¹ To date, agencies have utilized this authority only a handful of times, typically issuing regulations that either allow or prohibit specific trail uses for certain NSTs or NHTs under their jurisdiction.⁵²

Trail uses on nonfederal lands—whether scenic, historic, recreation, or connecting trails—are typically controlled at the state and local levels. Agencies have generally interpreted NTSA in a manner that considers all trail management activity on nonfederal land to be voluntary and that designation of a national trail, unless otherwise specified in law, does not place any restrictions or requirements on private landowners. Uses on nonfederal trail segments may still be limited through cooperative and certification agreements, easements, and actions by a range of entities, including nonprofit organizations. The terms of these legal agreements generally accord with NTSA and provide for the use of lands for trail purposes.

Funding

Total federal funding for national trails is difficult to calculate, because funding for trail operation, maintenance, construction, or land acquisition may come from a variety of sources. Each agency with management authority over national trails has its own funding for carrying out activities related to trail administration and management. Agencies do not always specify operational funding levels for individual trails in annual budget justifications.⁵³ Instead, funding for trails may be spread across a number of different budget accounts and activities. Even when agencies do break down individual trail operational costs (as NPS and FS have done), other federal funding may still be unaccounted for in these totals. For example, funding for trail land acquisition primarily comes from the Land and Water Conservation Fund, a mandatory spending account that may be allocated pursuant to either agency or congressional directives.⁵⁴ In addition, NRTs and connecting trails on federal lands are typically supported through the general operational budget of the particular unit (national park, national forest, etc.) on which the trail is located and therefore would not be included in the operational costs for the individual trail. Trails that cross multiple jurisdictions may receive funding from each of the agencies responsible for managing one or more segments of the trail. Generally, however, federal land management agencies have agreed—within the limits of agency authorities—to eliminate duplicate efforts and "increase effectiveness" by coordinating requests for and obligation of funds for the National Trails System.⁵⁵

In addition to funding from land management agencies, trails within the National Trails System may also receive funding from other federal agencies. Since 1992, the Department of Transportation (DOT), through federal transportation programs authorized by Congress,⁵⁶ has provided funding for bicycle and pedestrian transportation projects, including trail-related projects.⁵⁷ Although DOT does not manage or administer any national trails, this funding has typically been a significant funding source for national trails, as well as for the development and management of nonfederal trails across the country.⁵⁸

Additional sources of funding for trails may come from nonfederal sources. These include nonfederal matching funds in challenge cost-share projects, cooperative agreements with trail partner organizations, and donations from corporations, charitable foundations, and other groups. Volunteer and service organizations have also historically played an important role through in-kind contributions that help support the management and development of national trails both on and off federal land.⁵⁹

Issues for Congress and Recent Legislation

Issues related to trails and the National Trails System are of perennial interest to Congress. Congress regularly considers legislation that would amend the NTSA, establish new types of trails, add individual trails, extend existing trails, or direct agencies to study potential additions to the system (see Table 2). For example, in the 117^th Congress, two new NHTs were established: the Chilkoot NHT (P.L. 117-328) and the Butterfield Overland NHT (P.L. 117-345). In the 116^th Congress, the omnibus public lands act, P.L. 116-9, made or proposed a number of changes related to the National Trails System. Among the changes, the law adjusted the boundaries of the North Country National Scenic Trail, extended the Lewis and Clark National Historic Trail, and directed the study of a proposed Pike National Historic Trail running from Missouri through Louisiana. Another law in the 116^th Congress, P.L. 116-111, directed the Secretary of the Interior to study for potential designation the Emancipation National Historic Trail, a route from Galveston, TX, to Freedmen's Town and Emancipation Park in Houston, TX, that follows a migration route taken by newly freed slaves in the 19^th century.

When considering legislation that would potentially add or extend units of the National Trails System, Congress may evaluate specific questions or concerns raised by stakeholders—including private landowners—regarding the potential impacts that designation may have on future uses of land along or near a proposed corridor. Congress, at times, has included provisions in establishing legislation specifying that certain activities may not be prohibited, hindered, or disrupted as a result of designation as an NST or NHT.⁶⁰ Although agencies generally interpret the NTSA to require that management of private lands along a trail corridor be subject to landowner approval and consent, stakeholders have raised concerns regarding the potential reach of the federal government's authority.⁶¹

Another issue of congressional interest has been the amount or effectiveness of federal funding for the National Trails System. Stakeholder groups have advocated for increased funding, as well as dedicated line items in agency budgets to better achieve consistency in trail funding from year to year.⁶² Many of these groups point to concerns around the deferred maintenance backlog on trails and increased resource degradation due to visitation.⁶³ By contrast, some may view additional funding as potentially unnecessary, or feel that current funding levels are sufficient to meet management needs. Concerns have also been raised regarding perceived staffing shortages across federal land management agencies that, stakeholders suggest, impact agencies' ability to adequately manage trails under their jurisdiction.⁶⁴ The Inflation Reduction Act (P.L. 117-169), enacted in August 2022, included $500 million, to remain available through FY2030, for NPS to "hire employees to serve in units of the National Park System or national historic or national scenic trails administered by the National Park Service."⁶⁵

Congress has also considered proposals that would provide additional resources and directives to agencies to complete and/or connect existing national trails. As discussed above (see "Trail Development"), once Congress designates an NST or NHT, the administering agency is directed to begin establishing the rights-of-way for the established trail. For most of the congressionally designated NSTs and NHTs, such work is still in progress. Also, most of these trails are not continuous, even though trail continuity is one of the objectives of the NTSA. Congress has considered a variety of proposals aimed at addressing this issue. For example, in the 117^th Congress, the Complete America's Great Trails Act (H.R. 7913/S. 4346) would have amended the Internal Revenue Code to allow a tax credit for the fair market value of any NST conservation contribution. The bills also would have required the Secretary of the Interior to study the efficacy of such a tax credit in completing, extending, and increasing the number of NSTs. Other proposals would have directed administering agencies to complete specific trails, to the maximum extent possible, by certain dates.⁶⁶ Concerns have been raised regarding implementing these proposals, given that trail completion may largely depend on willing landowners consenting to connect the lands through means such as rights-of-way, access and conservation easements, and land acquisition.⁶⁷

Some bills would have adjusted the types of trails that could be designated in the National Trails System. For example, H.R. 726 in the 116^th Congress would have added "national discovery trails" to the system. National discovery trails would be extended, continuous interstate trails that provide for outdoor recreation and travel and that connect representative examples of America's trails and communities.⁶⁸ In addition, Members have introduced legislation that would have directed NPS to treat all NSTs under its administration as units of the National Park System,⁶⁹ as well as legislation that would have provided additional resources and funding for programs that aim to connect trails with underrepresented and/or urban communities.⁷⁰