A route that is designed, designated, or constructed for recreational pedestrian use or provided as an pedestrian alternative to vehicular routes within a transportation system.

A trail designed, designated, or constructed for pedestrian use may also have other uses, such as bicycling or in-line skating. It is recognized that pedestrians use all trails. However, these guidelines apply only to trails where travel on foot is one of the designated uses for which the trail was created. For example, a trail designated for mountain biking will not be considered a "pedestrian trail" whether or not pedestrians actually use the trail. However, a multi-use trail specifically designed and designated for hiking and bicycling would be considered a pedestrian trail. Trails include (but are not limited to) a trail through a forested park, a shared-use path, or a back country trail. Trails do not include pathways such as sidewalks, pathways in amusement parks, commercial theme parks, carnivals, or between buildings on college campuses. These exterior accessible routes are already covered by ADAAG 4.3.

The accessibility guidelines for trails apply to those which are designed and constructed for pedestrian use. These guidelines are not applicable to trails primarily designed and constructed for recreational use by equestrians, mountain bicyclists, snowmobile users, or off-highway vehicle users, even if pedestrians may occasionally use the same trails. People use these categories of trails by means of transportation other than foot travel or personal mobility device. Design and constructed requirements for equestrians, mountain bikes, OHVs, and snowmobiles are based on the specific requirements for the intended mode of transportation. For the safety of trail users, pedestrian use may not always be permitted on these trails in order to minimize conflicts between motorized and non-motorized recreation.These trails do not preclude use by a person with a disability since it is planned that all trail users would be using the one or more alternative means of transportation for which the trail is designed and constructed. The design and construction of pedestrian trails without consideration of these proposed guidelines, by contrast, could present barriers to some trail users because the intended use is by foot or personal mobility device. For these reasons, the committee intentionally limited the application of the proposed guidelines to pedestrian use trails.

It should be noted that the definition used in these proposed guidelines is not the only definition used by trail designers and manager. Rather, it was developed to specifically define the scope of these guidelines. Additionally, it is intended that trails and side trails leading to elements related to the trail, such as campsites and restrooms should meet the accessibility guidelines for trails not outdoor recreation access routes.


The proposed accessibility guidelines apply to all newly constructed and altered trails connected to accessible trails or designated trailheads. Since departures from certain technical provisions are permitted, it is important to clarify what is considered an "accessible trail." "Accessible trails" include those newly constructed and altered trails that meet all of the provisions of section 16.2. This includes the exceptions provided within each provision. It does not, however, include those exceptions within some provisions that allow for the provision to not apply due to one of the conditions in 16.1.1. Furthermore, only those trails that meet the provisions are required to be signed, indicating that they are accessible.

Designated trailhead.
A designated point of access that may contain a parking area, information kiosks, restrooms, water hydrants, and may be reached by vehicular or pedestrian access.

A designated trailhead is a "point of access" to a trail intended for public use where information may be provided. It may include a parking area, water hydrant, restroom, information kiosk, or other outdoor recreation elements. The designated trailhead may include vehicle a parking area for the public to access the trail or may connect from a sidewalk, or from a street or road in an area where pedestrian access from a nearby neighborhood may be expected. It does not include a junction between trails where there is no other access or a location where a trail crosses a road and public access from the road is not expected or is discouraged. It also does not include an access point not open to the public.

Tread Width.
The clear tread width of the trail is the width of the useable trail tread measured perpendicular to the direction of travel and on or parallel to the surface of the useable trail tread. The minimum clear tread width is the narrowest measurement on the useable trail tread with respect to a specific trail segment. Clear tread width differs from clear width in that the latter is the amount of land potentially available for the trail.


The committee considered many different approaches to developing accessibility guidelines for newly constructed and altered trails. Each approach balanced accessibility with the uniqueness of the outdoor environment. The following are examples of the approaches considered for trails throughout the committee's deliberations.

  • Requiring a percentage of the miles of trails provided to be accessible. Using this approach, it was agreed that some trails, such as paved urban and suburban transportation routes, should usually be accessible. But the committee could not agree on the types of trails, other than the type mentioned above, that should be accessible and to what percentage. The committee determined that this approach would be too arbitrary and too difficult to follow.
  • Requiring a percentage of the total number of trails to be accessible. The committee could not agree on a percentage. A significant issue was the difficulty in separating existing trails and new trails when determining the total number of trails.
  • Dividing trails into different categories (i.e. front country, back country) and requiring certain accessibility guidelines to be followed. The committee could not agree on the categories, nor could it agree that a trail in one category would always be different than a trail in another category. A fear in this regard was that only "easy" trails would be accessible, thereby eliminating the option for people with disabilities who can use more difficult trails, the opportunity to do so.
  • Requiring a certain level of access dependent on the location (i.e. highly developed, moderately developed, minimally developed) of the trail in terms of the type of setting. Definitions must be agreed to and understood by the trails community, people with disabilities, and land management agencies that are a part of the Federal government, States, and local entities. The committee could not find acceptable definitions for a "settings" approach.

Committee members evaluated each approach through extensive discussion and analysis. Within each proposal, the committee weighed the balance between accessibility and the uniqueness of the outdoor environment. Trails are often designed for a certain experience, or for the user or types of use within the setting. Primitive or back country trails for example, are usually found in remote locations or in a natural state with limited development. Throughout the discussions, committee members were concerned that providing access would change the experience or result in a significant environmental impact. Even providing accessible trails in a highly developed setting raised concerns that all trails would begin to look alike. Committee members did not want the proposed guidelines to impede the creativity of planners or designers.

As this discussion evolved, some concerns common to each approach arose regarding the potential impact on the natural environment. The committee attempted to clarify and define these concerns so that all involved (land managers, groups representing people with disabilities, and the trails community) could agree on these concerns. The result in 16.1.1 defines four specific conditions where trail construction projects can depart from the technical provisions. This departure is allowed for the duration of the existence of the condition, or unless that condition is such that it makes it impractical to make the remainder of the trail accessible.

When designed and constructed, an accessible trail is a trail that meets the technical provisions included within these proposed guidelines. It is also considered accessible where it one of the exceptions within the technical provisions are used to address a specific condition. This is limited to certain exceptions, and does not include those that allow for departure from the entire provision based on the conditions in 16.1.1


Where specified, the presence of these conditions included in 16.1.1 may also prevent full compliance with some of the technical provisions for elements in picnic, camping, and beach facilities. While the conditions for departures may be more limited with these outdoor elements, the committee included the option for departure in several provisions. In most cases, these are limited to technical provisions for clear space, surface slope, and accessible surfacing.

Where designers or operators depart from a specific technical provision because of one or more of the conditions previously identified, the other technical provisions should be applied. For example, a significant cultural feature may prohibit a 36 inch trail tread width. However, all other provisions could be met because they would not be affected by the condition.

The committee realized that there may be situations where the combination of factors and conditions may make it impractical to make the entire portion of the trail to be constructed accessible according to the technical provisions. The two general exceptions of 16.2 were developed to address these situations.

While the proposed accessibility guidelines address the special circumstances where designers and operators may not be able to achieve accessibility, they are encouraged to always provide access to the greatest extent possible.

Proposed 16.2 includes two general exceptions. First, where one or more of the conditions in 16.1.1 applies and where one or more of the conditions in this general exception applies, 16.2 shall not apply after the first point of departure. The segment of the trail between the designated trailhead and the first point of departure is required to comply with 16.2 unless the trail segment is 500 feet or less in length. If the trail segment connects to a prominent feature less than 500 feet from the designated trailhead, it is required to comply with 16.2 between the trailhead and the prominent feature.

The general exceptions are based on these parameters:

(a) The combination of running slope and cross slope exceeds 40 percent for over 20 feet; or,

(b) A trail obstacle 30 inches or more in height across the full tread width of the trail; or,

(c) The surface is neither firm nor stable for a distance of 45 feet or more; or,

(d) A clear trail width is less than 12 inches for a distance of 20 feet or more.

Second, where one or more of the conditions in 16.1.1 are met resulting in departures from the technical provisions in 16.2 for over 15 percent of the length of the trail, 16.2 shall not apply after the first point of departure. The segment of the trail between the designated trailhead and the first point of departure is required to comply with 16.2 unless the trail segment is 500 feet or less in length. If the trail segment connects to a prominent feature less than 500 feet from the designated trailhead, it is required to comply with 16.2 between the trailhead and the prominent feature.

The 15 percent threshold is a compromise, negotiated to balance the resources and environmental impact with the practicality of providing meaningful access on trails. The committee recommends that trail designers and managers attempt compliance with all technical provisions throughout the full length of the trail.

Proposed 16.2 also requires elements provided on trails to comply with these provisions. For example, if a bench is provided along a trail complying with 16.2, the bench shall meet the applicable provisions of 16.12. Where elements are provided along trails, they are not required to be connected by an outdoor recreation access route.

Question 4. Where pedestrian trails are not accessible, the committee could not agree on whether elements such as; benches, picnic tables, toilet rooms, etc., located on the trail, should be required to be accessible. For example, an element such as a picnic table may be located on a trail too steep to be accessible. The committee considered how future and existing technology will allow assistive devices to get over more difficult terrain. If required, they discussed options to minimize scoping (e.g. one of each elements) requirements or limit the requirement to certain elements such as sanitary facilities. The committee is requesting comment and/or options on this issue and whether elements located on inaccessible trails should be required to be accessible.


Proposed 16.2.1 requires the surface of accessible trails to be firm and stable. The "slip resistance" requirement was dropped from the accessible surface requirements of ADAAG 4.5 because slip resistance cannot be guaranteed in the outdoor environment. Weather conditions (rain, snow, ice) will affect slip resistance. For example, natural or non-hardened surfaces may not be slip resistant. Slip resistance may also be difficult to control when leaves and other surface debris caused by natural erosion accumulate on the surface.

The means and materials used to establish accessible exterior surfaces are plentiful. Crushed stone, fines, packed soil, and other natural materials can provide a firm and stable surface. Natural materials bonded with synthetic materials can provide the required degree of stability and firmness. An appendix note has been added to provide designers and operators with additional information concerning accessible exterior surfaces. An exception permits departure from this provision where one or more of the conditions in 16.1.1 exists.

Proposed 16.2.2 requires the clear trail tread width to be 36 inches minimum. This is consistent with the clear width requirements for an accessible route in ADAAG 4.3.3. Exception 1 permits the clear trail tread width to be reduced to 32 inches minimum where one of the conditions in 16.1.1 applies. Exception 2 permits departures from 16.2.2 where a 32 inch minimum width can not be provided because one of the four conditions in 16.1.1 exists.

Proposed 16.2.3 requires openings in trail surfaces to be of a size that does not permit the passage of a ½ inch diameter sphere. Elongated openings shall be placed so that the long dimension is perpendicular or diagonal to the dominant direction of travel. Exception 1 permits elongated openings to be parallel to the dominant direction of travel where the opening does not permit passage of a 1/4 inch diameter sphere. This is necessary to allow trail managers to place boards lengthwise along a boardwalk trail to reduce the environmental impact such as on a wetland area.Exception 2permits openings that do not permit passage of a 3/4 inch diameter sphere where at least one of the conditions in 16.1.1 apply. Exception 3allows departure from the provisions of 16.2.5 where openings that do no permit passage of 3/4 diameter sphere are not feasible because at least one of the four conditions in 16.1.1 apply.

A 3/4 inch spacing is permitted through an exception since many trails use wood plank decking or boardwalks to cross wet, sandy, rocky, or environmentally sensitive areas. The planks expand and contract because of weather conditions. The boardwalks may need more than ½ inch spacing between the planks to permit expansion and to allow water to drain.

Proposed 16.2.4 requires protruding objects on trails to comply with ADAAG 4.4.1 and shall have 80 inches minimum clear head room. Where the vertical clearance of a trail is reduced to less than 80 inches because one of the four conditions specified in 16.1.1 applies, an exception provides that a barrier to warn blind and visually impaired persons shall be provided. This allows a trail to pass through narrow, winding corridors, under ledges or through caves to provide these experiences. This provision represents a compromise reached by committee members, and is essentially what is required by ADAAG 4.4.2. Some committee members saw the need for a departure from a minimum 80 inches overhead clearance, while others felt that permitting this could present barriers to people with visual impairments.

Question 5. The committee could not reach consensus on allowing a complete departure from this provision if the minimum overhead clearance could not be provided along a trail. After some debate, the committee agreed to propose the requirements of ADAAG 4.4.2. Providing such a warning along a trail in the outdoor environment may have the effect of creating a barrier for all trail users. The committee is requesting comment and/or other options available on trails, specifically where there is a lack of sufficient space to move around an obstruction without significantly impacting the natural environment or setting.

Proposed 16.2.5 replaces ADAAG 4.5.2 (changes in level) and requires that any tread obstacles shall not to exceed 2 inch maximum in height. Exception 1 permits a 3 inch obstacle where the running and cross slopes are 1:20 or less. Exception 2 permits obstacles greater than 3 inches where at least one of the conditions in 16.1.1 apply. The committee recognized that natural features such as rocks, roots, and ruts may require a greater obstacle height than what is permitted in the indoor environment. Some wheelchairs used in an outdoor environment are designed to handle obstacles of these heights. However, trails used by bicyclist or in-line skaters or which serve as alternate transportation routes for sidewalks should be smooth with no abrupt changes in level.

Proposed 16.2.6 requires passing space where the clear tread width of the trail is less than 60 inches. Passing space is required at intervals of 1000 feet maximum. Either a T-shaped or a turning circle is permitted. An appendix note states that the passing space may be located to one side of the trail. An exception permits departure from this provision where passing space cannot be provided because at least one of the four conditions in 16.1.1 exits.

The committee negotiated various intervals for passing space, ranging from 200 feet (current ADAAG 4.3.4) to no requirement. Those favoring longer intervals or no requirement explained that the outdoor environment often allows users to move off the trail tread without involving trail construction (as opposed to being restricted by walls within a building). There was concern about having an unrealistic construction requirement in a natural setting, and concern that requiring a constructed passing space at more frequent intervals may be unnecessary where few users are on the trail at the same time. An appendix note is added recommending that trails expected to have higher use and trails with long sections where it is not possible to move off the trailhead (e.g. boardwalk in wetland) should consider more frequent passing spaces, especially close to the trailhead.

Proposed 16.2.7 addresses both the cross slope and the running slope of the trail. This provision was the result of significant compromise among committee members. Exception 1 addresses open drainage structures. For open drainage structures, a running slope of 14 percent is permitted for 5 feet maximum with a cross slope of 1:20 maximum. Cross slope is permitted to be 1:10 at the bottom of the open drain, where the clear tread width is 42 inches minimum. Exception 3 permits departure from 16.2.7 where one or more conditions of 16.1.1 exists.

Proposed requires that the maximum cross slope of trail segments not exceed 1:20. Committee members recognized that cross slopes, or the side-to-side slope of a trail, can be difficult to traverse. At the same time, trails need to be designed to provide sufficient drainage to prevent ponding and water damage to the trail. Non-paved surfaces generally require more than a minimum of 1:50 cross slope.

Proposed addresses the maximum running slope of trail segments. Proposed 16.2.7 permits no more than 30 percent of the total trail length to exceed a 1:12 slope. The committee debated various slope ratios for this provision. Committee members advocating steeper slopes were concerned that requiring unrealistic slopes in natural areas which could significantly alter the natural terrain. Members advocating less slopes were concerned that steeper slopes would not be accessible, and could be a potential safety hazard.

Proposed requires that trails comply with one or more of four separate provisions. Designers may choose which provision to apply. Proposed permits running slope at 1:20 or less for any distance. Proposed permits a running slope of 1:12 maximum for 200 feet maximum. Resting intervals complying with 16.2.8 shall be provided at distances no greater than 200 feet apart. Proposed permits running slope to be 1:10 maximum for 30 feet maximum. Resting intervals complying with 16.2.8 shall be provided at distances no greater than 30 feet apart. Proposed permits running slope to be 1:8 maximum for 10 feet maximum. Resting intervals complying with 16.2.8 shall be provided at distances no greater than 10 feet apart.

Because the terrain in outdoor environments is often steep, the committee realized that applying current ADAAG slope and ramp requirements was not feasible. The proposed running slopes and maximum distances represent a compromise reached among committee members and balances accessibility with the constraints imposed by natural topography.

Question 6. Proposed 16.2.7 permits departure from the technical provisions for cross slope with open drainage structures. A cross slope up to 10 percent is permitted at the bottom of the open drain, where the clear tread width is 42 inches minimum. Are open drainage structures the only drainage structures where cross slopes up to 10 percent should be permitted? If not, what other areas should be identified.

This section also modifies existing ADAAG with respect to the use of handrails, since trail slopes are addressed in this section and not by ADAAG 4.8. Handrails are not required on trails. The committee believed that handrails were impractical in this environment. In addition, steeper grades on trails are usually contiguous with the surrounding terrain rather than elevated above it as with a ramp to a building. Instead, the committee has limited the length of steep portions of trail segments and required resting intervals. It was believed that this was more practical in the outdoor environment.

Proposed 16.2.8 requires resting intervals to be 60 inches in length to accommodate wheelchair users, and at least as wide as the widest portion of the trail segment leading to the resting interval. The slope of the resting interval shall not exceed 1:20 in any direction. An appendix note recommends that the resting interval may be located to one side of the trail to allow other users to pass. An exception permits departure from this technical provision where one of the conditions in 16.1.1 exists.

Proposed 16.2.9 does not require edge protection on accessible trails, however, where it is provided, the height shall be a minimum of 3 inches. Natural trail surfaces are likely to have variations in the trail surface, and a 2 inch edge protection may not be obvious or detectable in the outdoor environment. In the outdoor environment, many people with limited vision who use canes will search higher than in an indoor environment to distinguish between the edge and variations within the trail.

Proposed 16.2.10 requires signs on newly constructed and altered trails and trail segments that comply with all the technical provisions of 16.2 to be designated with a symbol at the trail head or designated access points. An example of a potential sign to be used at accessible trails is included in the appendix. Signs identifying accessible trail segments shall include the total distance of the accessible segment and the location of the first point of departure from the technical provisions.

Signs for trails were extensively debated by the committee. While certain trail information is critical for users, there was concern about requiring too many signs with too much information. There were also concerns that the requirement may be too onerous in terms of providing detailed information about trail characteristics. As a compromise, the committee agreed to include a requirement for a symbol to identify those trails that are accessible. Additionally, where the symbol is used to identify accessible trail segments, the total distance of the accessible trail segment to the location of the first point of departure from the technical provision must be provided.

An extensive appendix note has been provided on the issue of trail information. The appendix note includes recommendations for the types of information which should be provided and examples of different formats for providing the information to users. Where trails are provided and conditions have required departure from some of the technical provisions, it is recommended that more detailed signs be provided to help users make informed decisions about trail use.

Question 7. Some examples of proposed signs designating accessible trails are included in the appendix of this report. The committee did not reach a consensus on a particular sign and is requesting specific comment on these signs and/or other options. The proposed guidelines for trails require a sign on trails that meet the provisions and exceptions of 16.2.