The three things worth reading before a tent comes out of its bag are drainage, wind, and history, and they get read in that order because each one can overrule the one before it. Ground that sheds water is no help if you pitch in a notch where the wind accelerates at two in the morning; a spot that is perfectly sheltered and bone dry is often dry because it is a well-used campsite, and that changes which patch of it you should actually occupy. The whole read takes a few minutes on foot, and it decides whether the pitch is one quiet operation or a long night of sliding toward the low corner of the floor.
I do it with the pack still on, because the second the pack is down, the site starts looking better than it is.
First pass: what the last hard rain left behind
I walk the site instead of standing in it. Head down, slow, reading the ground the way you read a page when you're hunting for one word.
What I want is a line. A stripe of pine needles laid across the duff in a direction the surrounding litter doesn't share. Fine silt or sand dropped on the downhill side of a rock with the leaves plastered flat against its uphill face. If it's a shallow braid instead of a single channel, that's even more useful, because braided flow means the water spreads and comes back rather than running off cleanly. Those marks are what the last storm did here. They're also a decent forecast of the next one.
Then I press with a palm, and then with a heel. Duff that gives and springs back is duff that absorbs. An inch of needles over ground that's slick and hard underneath is compacted soil, and compacted soil sheds water instead of drinking it. That sounds helpful until you notice it's shedding toward the lowest point in the site, and the lowest point in the site is where your floor is going to sit.
I don't use moss. Moss on the north side of a trunk is one of those rules that works in some forests and lies in others, and I've been in too many stands where the moss was everywhere to trust it. Litter that's still glossy and unbleached tells me about shade and moisture, which is worth knowing, but it doesn't tell me which way the water goes.
Compacted ground never looks compacted from a standing height. Crouch.
The flattest spot in the site is usually the lowest one
Every campsite has an obvious flat spot. It's usually the one that's been slept on the most, and it's usually the lowest thing within thirty feet, because flat ground in the middle of a grade is either a filled depression or dirt that got beaten down into one over years of use. Standing water isn't required for that to ruin your night. Ground that stays saturated stays cold, and a cold floor pulls heat out of a sleeping pad faster than cold air does.
Sleeping on a two- or three-percent grade, a rise of a few inches over the length of your body, is more comfortable than flat ground and drains better. Water that lands on a slope leaves. Water that lands on level ground sits there until it soaks in or evaporates, and both of those take hours you don't have.
The direction matters as much as the amount. Head uphill. Your shoulders and hips will find the low point no matter what you tell them, so give them the high end and let your feet hang slightly downslope. If the grade is steep enough that you have to brace, it's too steep, and you're better off shifting two feet sideways than fighting it.
There's a second kind of drainage I check, and it's about air rather than water. At night, air near the ground cools, gets denser, and drains downhill like a slow liquid. A flat bench near the bottom of a bowl is the coldest place on the mountain. So is a flat spot in a hollow, even a shallow one. If the air feels heavier and colder than it did a hundred yards up the trail, and the duff smells wet, you've found a cold pool, and your sleeping bag is going to work harder all night for no reason.
Look up before you look down
Before anything gets staked, I stand at the spot and look straight up for a slow count of ten.
Dead limbs still attached are the ones that come down. A branch lodged in the crotch of a live tree is a branch that's been waiting. Standing dead snags, especially ones with bark starting to peel, are the obvious case, but the one people miss is the healthy-looking big tree, because the biggest tree in a stand has the most material overhead to lose. I don't sleep under it. Not because big trees are unstable, but because the odds are distributed with the mass.
Wind is where the terrain read pays off most. Natural blockage, a hedge of shrubs, a trunk line, a rise in the ground, all of it slows moving air at tent height. Saddles between two high points, gaps in a ridge, and the mouth of a drainage do the opposite; they squeeze air through and speed it up. Two sites a hundred yards apart can see completely different wind just because of what's between them.
Here's the part that catches people. The wind you feel at six in the evening is not the wind you'll get at two in the morning. As the air cools and drains downhill, a site that was dead calm at dusk can have a steady downhill breeze running through it after midnight. When I have two candidates, I pick the one with something between it and the downhill direction, not the one that feels calmest right now.
The tradeoff is real, and I won't pretend it isn't. The sheltered spot is often the damp spot. Wind moves moisture away. Dense canopy blocks sun, holds humidity, and drips on you an hour after the rain stops. If the shelter is heavy canopy over soft duff, I'd rather take a little more wind and a firm, sloping floor. Wind you can manage with a low pitch, a tight fly, and a door on the right side. A wet, cold floor you can't manage at all.
Where the ethics and the drainage read disagree
This is the part that generic site-selection advice usually skips, and it's the part that actually requires a decision. The best-draining ground is almost always ground nobody has walked on. Ground nobody has walked on is exactly what Leave No Trace asks you not to sleep on.
Concentrating use on durable, already-impacted surfaces is the principle, and it exists because a new tent pad in a recovering forest floor costs far more than a night on dirt that's already bare. Seedlings, soil structure, and root mat all take a hit that a heavily used site has already absorbed. So the drainage read doesn't get to win outright. What it gets to do is happen at a smaller scale.
I use the established site, and then I walk within it. High point of the bare area, not the middle. The edge where packed dirt still holds a little grade, not the dished-out center. I move rocks and sticks off the footprint and put them back where they came from before I leave. I don't trench around the tent, ever. A drainage ditch is a scar on ground that's already working hard to recover, and one that does less for you than moving two feet uphill. I don't pull vegetation, and I don't build a new fire ring, which mostly means I don't have a fire.
On distance from water and from established trails, the widely published guideline is to keep well back, and the specifics shift depending on who manages the land. Worth knowing before you go rather than reading off a sign at dusk.
The last decision is which way the door faces
By the time I've read the ground, it has already told me which way to sleep and roughly where the tent goes. The door is the only free choice left.
I set it away from the wind I expect at two in the morning, which is usually the downhill direction, not the direction the afternoon breeze was coming from. If there's a choice after that, I face it toward open ground, the view if there is one, or the easier exit if the terrain around the site is rough. A door that opens into a wall of brush means you crawl out over the corner of the floor every morning, and you'll be doing it in the dark at least once.
Then I pitch the tent the ground wants rather than the one in the diagram. If the only usable grade runs diagonal across the site, the tent goes diagonal. If the wind is hitting the long side, the low end goes into it. I guy out what needs guying, not every point the manufacturer printed, because extra lines are extra things in the dark and more anchors driven into ground that doesn't need them. I use a stake or a rock before I wrap a line around a trunk.
Two last things I check on the footprint itself. Ant mounds show up as slightly raised cones of fine soil in the litter with a hole at the top, and a tent pitched over one gets visitors all night. Game trails show up as a worn narrow line of packed ground, often with browsed edges and scat, and they're easy to miss because a good trail looks exactly like the flattest, cleanest patch in the whole site. If the site has one, someone built it. Something walks it.
I lie on top of the unrolled pad before I inflate it. If I feel a rock, the rock moves. If I feel the grade, that's correct. Then I inflate, crawl in facing uphill, and the tent is already pointed the right way for morning.
