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Structural ridgeline

Also called fixed ridgeline, hammock ridgeline

What is a structural ridgeline on a hammock?

A structural ridgeline is a fixed length of cord tied between a hammock's two gathered ends. Because it cannot stretch, it holds the hammock at one repeatable amount of sag no matter how far apart the trees are, so the bed feels the same at every campsite.

Structural ridgeline at a glance

Typical length
About 83% of body length
Added weight
Roughly 1 oz
Cost to add
About $25
Fixes
Sag changing with tree spacing

What problem it solves

Without one, the shape of your hammock is decided by how far apart the trees happen to be and how hard you pulled the straps. Trees eleven feet apart give you one bed. Trees eighteen feet apart give you another. So you end up re-tensioning by feel, in the dark, after you've already climbed in.

A structural ridgeline takes that variable out. The cord is shorter than the hammock, so once the suspension is tight enough to pull it taut, the hammock has reached its designed sag. Any tension past that point goes into the ridgeline and the trees instead of flattening your bed.

How long should it be

The figure the hammock community has settled on is roughly 83 percent of the hammock's body length. On an eleven-foot hammock that's about nine feet two inches. Go shorter and the hang gets deeper and more curved. Go longer and it flattens and tightens, which brings back the shoulder squeeze you were trying to avoid in the first place.

Some makers build one in and set it for you. Hennessy has done that for decades and treats it as core to the design, alongside the asymmetric cut, and ENO's JungleNest and several Onewind hammocks include one too. Adjustable versions let you tune the sag. Fixed ones just hold the maker's number.

The other things it gives you

It's also somewhere to hang things. A ridgeline organizer, a headlamp, damp socks and a phone all live on it, and in a hammock that's the only storage there is. It's the cheapest upgrade in hammock camping: an ounce of cord and about twenty-five dollars if your hammock doesn't already have one.

What this means when you're choosing

  • Whether it is included, because most bare hammocks ship without one
  • Adjustable versus fixed, if you want to tune the sag rather than accept it
  • A rating well above your body weight, since the line carries real load
  • Attachment points or an organizer sleeve for hanging small items

The common mistake

Setting it too long to get a flatter bed

Lengthening the ridgeline pulls the hammock flatter, which sounds like a good idea right up until you lie in it. A flat gathered-end hammock squeezes your shoulders and pushes your feet up. If the hang feels wrong, shorten the ridgeline and lie further off the centerline instead of tightening everything.

Common questions

Do I need a structural ridgeline?

You can hang a hammock without one, and plenty of people do. What it buys you is repeatability: the same bed at every site, with no re-tensioning by feel. If you're sleeping in a hammock rather than lounging in one, it's the cheapest upgrade that actually changes how you sleep.

Is a structural ridgeline the same as a tarp ridgeline?

No, though they're easy to confuse, since both are cords running the length of the setup. A structural ridgeline runs between the hammock's own two ends and sets its sag. The tarp ridgeline is the one over your head, strung tree to tree, with the tarp hanging off it.

Where this is defined

Where this comes up

Guides on Tom's Hiking where structural ridgeline changes which product is right for you.

More in shelters

Freestanding tent

A freestanding tent holds its shape on its own poles without needing stakes to stand up. You can pitch it on rock or a wooden platform, pick it up to move it, and shake it out, none of which a staked shelter allows.

Trekking-pole tent

A trekking-pole tent uses the poles you're already carrying as its structure, so it ships without a pole set. That removes a pound or more from the pack, and requires stakes and taut guylines to stand up at all.

Vestibule

A vestibule is the covered space between a tent's inner door and its fly, outside the sleeping area but under shelter. It's where boots, packs and wet gear live, and where you can cook in bad weather if you're careful.

Footprint

A footprint is a shaped sheet of fabric that goes under a tent to protect the floor from abrasion and punctures. It's almost always sold separately, and a piece of polycryo or Tyvek does the same job for a fraction of the weight and cost.

Trail weight

Trail weight, sometimes called minimum weight, counts only a tent's essential parts: inner, fly and poles. Packed weight counts everything in the box, including stakes, guylines, stuff sacks and instructions. The gap is usually several ounces.

Bathtub floor

A bathtub floor is a tent floor whose waterproof fabric curves up the sides several inches before meeting the walls, so the seams sit above ground level. Water running under the tent has no seam to get through.

Gathered-end hammock

A gathered-end hammock is a flat rectangle of ripstop nylon bunched to a single point at each end and hung from two trees. It is the standard camping design, and it only lies flat if you sleep diagonally across it rather than down the middle.

Double-wall tent

A double-wall tent is built as two separate layers: an inner body, usually largely mesh, and a waterproof rainfly over it. Condensation collects on the underside of the fly instead of on the surface you and your bag are touching.

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