This is a hiking trail.
When you look at it, or any other trail for that matter
It can feel sort of organic.
Like nobody in particular decided what it should look like.
But behind almost every trail
are planners, builders, and designers crafting an experience
that gives people a tiny taste
of what real wilderness feels like.
And when they do their job right...
it can feel like they were never there.
It begins with trying to understand
the visitors who will be using the trails.
Jeff Marian studies the design of trails
and how they fit into the environment.
People seem to really want to hike on
native surface trails, you know, in pristine nature
not highly altered, highly developed nature with pavements
and things like that.
So what makes a trail feel like pristine nature?
For one thing, there's its shape.
Unlike paved roads, trails are often built to mimic
the imperfect natural patterns of branches, waterways, or lightning.
There's also the features a trail connects with along the way.
Designers will often build a trail so it touches anchors —
vertical features like large rocks or trees
that create a pleasant frame on the edges of a trail.
They also have to decide where it goes.
So you sit down on your map
and you map out these control points.
Designers will identify the places people shouldn't go.
Like hazardous zones, private property
and environmentally sensitive areas.
And the places they should.
Like scenic overlooks, waterfalls and lakes.
These are called negative and positive control points
and they give a rough idea of where a trail can go
making sure a trail goes to the places
where hikers will want to go is essential
because if a trail doesn't
curious hikers will find their own way to them.
Creating desire lines that branch off from the actual trail.
Those desire lines can disrupt water systems, plants
or wildlife in ways the trail designers didn't account for.
And that's the paradox of trail design.
They're artificial creations
that need to feel like they're part of nature
but also need to accommodate visitors
all without deteriorating over time.
Designers spend a lot of time thinking about this.
But the force they're most concerned about protecting trails from
actually isn't people.
It's water.
Water is the natural enemy of a manmade trail.
It can erode a trail away,
make it too muddy to use,
or change the shape of it completely.
So we try to design trails
to be sort of invisible to that water flow
and that movement of water across the landscape.
So hydrologically invisible.
To do that, look at topographic maps
which illustrate the landscapes elevation.
And they look at the fall line.
That's the line that water follows as it flows downhill.
If you dumped a bucket of water on the ground on a slope
it would run straight down the fall line.
If a trail runs parallel to the fall line or too close to it
it becomes a pathway for water when it rains.
The trail then sort of acts as a drainage ditch
going straight down the hill.
Over time, that causes the trail to erode and become wider.
But a trail that runs perpendicular to the fall line isn't good either
because then water can't flow downhill at all.
If it's dead level, it's going to sit there
and make a big, huge mudhole.
It's mostly just, you know, poor design.
Instead, a good trail runs diagonal to the fall line
cutting up a slope at an angle and allowing water
to flow across the trail instead of down it.
And accounting for the fall line is just one of the principles
designers look at to manage water on trails.
There's also grade reversals where a trail alternates
between short, uphill and downhill sections.
This creates little valleys
where water can flow off of a trail
in smaller quantities.
There's the slope
which, when it stays between a 3% and 10% grade
is both comfortable for hiking and minimizes erosion.
There's the out slope, a slight downhill tilt on the trail
that helps water flow downhill.
And there's the tread: the stuff the trail is actually made of.
The higher the proportion of rocks, the better it can resist erosion.
This careful combination of alignment, materials, and shape
can help a trail last through years of impact...
even as those impacts become bigger than they've ever been before.
We're getting bigger rain events
and they're having a real toll on trails.
And so trail sustainability needs to focus way more on tread drainage these days
than we ever used to.
A lot of the work that trail designers do
isn't actually coming up with new trails.
It's strengthening and updating old ones
many of which have been around
since before recreational hiking was even something people did.
It's challenging.
It's not rocket science, but it is challenging.
It requires kind of an ecological knowledge
of the inner relationship
of a wide number of different factors.
Out on a trail, these factors add up to an experience...
a feeling...
of seeing a world that we didn't make.
It's a world we don't often have a way to see
and a good trail is our ticket in.
finding.