Information and examples of barriers, lights, pavements
and landscape treatments for historic roads.
Anatomy of a Historic Road
Every historic road is comprised of three parts: the road,
the right-of-way and the setting.
The road is the physical construction or resource that
has been designed or traditionally used for the movement
of people and goods. The road is composed of the following
The travelway refers to the area of the road dedicated to
the movement of vehicles. This may also be referred to as
a “carriage way” or “travel lane”.
Pavement is the durable or semi-durable surface of the travelway.
Pavement may be dirt, gravel, wood (logs lain side-by-side
to create a “corduroy” road or wood blocks),
stone (cobblestone or granite Belgian-block), brick, macadam,
concrete or asphalt.
Alignment refers to the horizontal or vertical movement
of the road. More specifically, horizontal alignment refers
to a road’s movement to the left or right—its
curves, and vertical alignment refers to a road’s
movement up and down—its hills. Horizontal and vertical
alignment may, of course, overlap.
Subsurface refers to the stabilized base beneath the pavement.
The subsurface provides both a stable base to support the
pavement and a finished surface on which to lay or adhere
the pavement. It is the subsurface that comes in contact
with the ground.
The crown of a road is a rise or upward arc toward the center
of the travelway that provides for drainage. Water is directed
away to a gutter, shoulder or swale.
A curb is a raised face at the edge of the travelway or
gutter. Generally 6-12” in height, a curb provides
a physical barrier between the travelway and the adjacent
sidewalk or landscape.
A gutter is a channel at the edge of the travelway designed
to collect and direct surface or rainwater away from the
road. Gutters are generally concrete or brick.
A shoulder is a stabilized surface that runs parallel to
and is flush with the travelway. In general a shoulder is
utilized for higher speed roads without a curb and gutter.
It varies in width and may or may not be constructed of
the same material as the travelway. Shoulders are generally
viewed as a safety feature—allowing for a disabled
vehicle to move out of the traffic in the travelway.
The road may be associated with essential structures that
are integral to its design and function. These may include
bridges, culverts, tunnels, tollbooths and retaining walls.
The right-of-way is composed of the elements and structures
that are immediately adjacent to the road and enhance its
function, use or safety, or utilize the publicly held lands
or easements associated with the right-of-way for other
public services (utility poles for example). Elements associated
with the right-of-way include:
A swale is a slight depression or ditch parallel to the
road that serves as a collector for rainwater runoff.
A barrier is a safety feature designed to protect the vehicle
from a hazardous situation. Barriers are commonly constructed
as guardrail, walls, or posts.
Lighting refers to both the source of light and its intensity,
and the design of the fixture that supports the light source
Road related signs provide information for the traveler
about road identification (route numbers), location, direction,
distance, warnings and regulations. Signs may also provide
visitor information, serve as commemorative or gateway features,
or provide visitor orientation.
Sidewalks are durable paved surfaces that run generally
parallel to the road and are dedicated to the use of pedestrian
(and sometimes bicycle) traffic.
Paths provide access for pedestrians and bicycles and are
generally less formally defined than sidewalks. Paths may
originate from an unplanned or organic use (people tend
to create paths if no other accommodation is provided),
or may have been designed. Paths may be unpaved or have
a gravel or asphalt surface.
A tree lawn is the area between the curb and sidewalk usually
dedicated to the planting of street trees.
Street trees are trees planted parallel to and generally
in a formal pattern or spacing, to the road.
Utilities may be above or below ground and include electric,
cable, telephone and fiber optic lines; gas, water, irrigation,
storm and sewer pipes; and transformers, service boxes and
Structures within the right-of-way may include bridges and
aqueducts that carry other roads, railroads or water over
the road. They may also include administration buildings
(often associated with toll roads and bridges) or inspection
structures (border facilities and agricultural inspection
Service areas may include highway maintenance yards, rest
areas or driver/auto plazas providing fuel, food and information.
waysides and overlooks
Waysides and overlooks are pull-offs adjacent to the road
designed to provide access to a scenic view, interpretation
or historical markers, or picnic tables. Such facilities
are generally without restroom facilities.
The setting refers to the area beyond the right-of-way.
The elements comprising the setting are often the features
we most associate with a road and use to determine if a
drive is pleasant or unpleasant. Elements defining the setting
Road-related features include structures and spaces that
are integral to the design and use of the road. Structures
may include gas stations, motor courts, drive-ins, taverns.
They may also include fanciful architecture designed to
capture the attention of the motorist.
Landscape features include parklands, natural areas and
plantings designed in conjunction with or resulting from
the creation of the road.
Character refers to the nature of the landscape or community
through which your road passes. It may be rural, suburban
or urban in nature. It may be local in character—tidy
bungalows with neat lawns—or it may be more regional
in character with businesses catering to the needs of the
traveler. Character may be reinforced through common or
repeating elements that create identifiable, even unique,
patterns, colors, and styles along the roadside.
Viewshed refers to the “view” from a particular
point in space. The viewshed encompasses everything that
can be seen by the naked human eye from this point. A viewshed
my be very large, such as the view across a valley from
a ridge road, or the view stretching across the great plains
to the horizon. It may also be very narrow such as the view
from a city street, no wider than the sidewalk and terminated
by the façade of an adjacent building, or the limited
view along a road in a densely wooded area. The viewshed
of a road is generally considered the view to the left or
right from the centerline of the road.