The gear you actually need for multi-pitch: half ropes, a rack, anchor material, helmet and emergency kit — compact, sensible and without overspending.
The honest answer to "What do I need for multi-pitch climbing?": clearly more than in the gym, but less than the shop wants to sell you. For your first bolt-protected plaisir routes a compact, well-thought-out rack is enough — the huge nut-and-cam collection comes later.
The key difference from the gym: in the gym you need a harness, shoes, a rope and a belay device. On the mountain you carry your entire protection system yourself — from anchor material to the rappel rope to the emergency kit. Every piece has a job, and you need to know which.
Start at the head, literally: the helmet is not optional on the mountain. In the large Austrian analysis the head, at 21.2 %, was one of the most common injury sites — rockfall and head-first falls are real, and a helmet is the cheapest life insurance you can buy.
And a second number that makes one gear detail lifesaving: more than half of all lowering and rappel accidents happen because a rope end shoots uncontrolled through the device. The countermeasure costs nothing — a knot in every rope end. Remember that now, before we get to rappelling.
Bolt-protected plaisir multi-pitches need no removable protection yet. Rope, harness, helmet, belay device, anchor material, draws and a prusik — that's enough. Buy removable protection only when the routes demand it.
A single rope is simple and cheap — good for short, straight plaisir routes. Half ropes are the alpine workhorse: less rope drag on zig-zag routes and double the rappel length. If you plan to stick with alpine climbing, half ropes are the better investment.
Rack nuts, cams, slings and carabiners in a fixed order — for example cams by size front to back. Searching for gear on steep ground costs strength and time. Order on your harness is safety in practice.
Sling, cordelette and the HMS carabiners belong in a fixed spot you can find blind. At the anchor you want to build, not rummage.
Confirm everything is there, inspect the rope and slings for wear, don't forget the prusik and first-aid kit. A quick gear check the night before saves nasty surprises on the mountain.
Two things are lifesaving on the mountain and cost almost nothing: the helmet — because the head is among the most common injury sites — and the knot in every rope end before every rappel and lower. More than half of lowering/rappel accidents come down to a too-short rope slipping through the device. Both are habits, not gear questions.
Inspect your material regularly: ropes age from UV, falls and abrasion; slings and cords lose strength over the years even unused. When in doubt, retire it — your life literally hangs on the weakest part.
Build yourself a fixed gear spot on the harness and drill it in your living room until you grab every piece blind: cams left by size, draws right, anchor material at the back, HMS carabiners on a marked loop.
Sounds fussy, but it is worth gold. At a steep anchor, with cold fingers and time pressure, you don't want to search — you want to grab. Climb your rack blind and you move faster and with more mental reserve.
For short, straight, well-bolted plaisir routes a single rope is fine. As soon as routes wander or you need full-length rappels, half ropes are clearly superior: less rope drag and double the rappel distance. If you want to stick with alpine climbing, half ropes serve you better long term.
Budget several hundred euros for a solid base set — half ropes, harness, helmet, belay device, anchor material, draws and a prusik. Removable protection (nuts, cams) is added later. Rent expensive gear to try things out before buying everything at once.
Not at first. You climb bolt-protected plaisir multi-pitches with draws and anchor material. You only need nuts and cams once you start on routes that aren't fully bolted — and then thoroughly practised, because a badly placed piece won't hold.
Ropes and textile gear age from UV, abrasion and falls — not on a fixed calendar but by use and condition. Rule of thumb: retire on visible damage, hard falls or after many years. When in doubt, replace it; the weakest part sets the safety of your whole chain.
Alpine Climbing: Building Anchors — Bombproof Belays on the Wall