Monuments and where they go

This page is about Rust’s own behavior, not Creator’s. When the game generates a world it does not drop monuments anywhere flat: each one has to pass a chain of checks, in order, and every one of those checks is something you take on yourself the moment you place a monument by hand.

The tiers

Monuments are classified by the tier of loot they hold, which also tracks their size, their radiation and how hard they are.

Tier	What it holds	Examples
Primitive	The weakest items, basic gear, no radiation	Roadside and forest sites, small fishing and trading spots
Tier 1	Simple components and basic gear	Mining Outpost, the gas station, the supermarket
Tier 2	Advanced components, military gear	Airfield, Water Treatment, Trainyard
Tier 3	Explosives, rare components, the best gear	Launch Site, Military Tunnels, the missile silo, Arctic Research Base

Higher tiers are bigger and rarer. A normal map carries one or two of the biggest Tier 3 monuments, not several. The tier split is also what the Tier Percentages sliders in Creator’s generator are dividing up.

What makes a spot valid

The generator tries candidate positions and runs each one through the same chain. It stops at the first failure, which is why a monument you expected sometimes simply is not there.

1. Spacing, first. How far this candidate is from every monument already placed: a minimum distance from others of the same kind, and a separate minimum from monuments of other kinds.
2. A dedicated gate for anything with a train tunnel entrance. Every monument that carries an entrance to the underground network has to stand at least 540 m from every entrance already placed, measured in three dimensions. Accepted entrances are then snapped onto the tunnel grid, and the whole monument moves with the snap.
3. The topology filter, at the center. Each family of monuments requires some topology flags and forbids others. This is the check that puts things where they belong.
4. The same filter again, at every one of the prefab’s own check points. A monument carries a set of points spread over its footprint, and the filter is run at each one. A candidate where any point reads zero is rejected. So the requirement is not “the middle of this monument is on the right ground”, it is “the whole footprint is”.
5. Flatness, at those same points. They are a slope and height check as well as a filter site.

The lighthouse is the clearest example of the chain doing its job. It stands offshore because its family filter requires the Ocean topology flag and forbids cliff, beach, beachside, forest, road, rail, river, swamp and building, and its check points tile its entire footprint. So the whole base has to be on ocean, not even on sand. Its exact seat at sea level comes from a separate rule that floats offshore decor to the waterline.

One thing the chain does not contain: a water check. No monument that the generator places uses one. An offshore or shoreline seat is always explained by topology flags, the footprint checks or the sea-level rule, never by a test for water.

How a monument sits in the ground

A placed monument conforms the terrain to itself, using masks that were baked into the monument when it was made: a height mask, a splat mask, a biome mask, a topology mask and an alpha mask. There is no separate smoothing pass that blends a monument into a hillside. The masks are the seating.

On the current build the monument’s anchors gate whether a candidate is accepted but do not set its final height: an accepted monument sits at the raw terrain height of the candidate position. One visible consequence is that monuments whose authored height mask sits above their own root build a proud pad by design. The missile silo’s mound is the extreme case, and it is intentional rather than a defect.

What this means when you place one yourself

Placing a monument by hand skips every check above, so the seating and the spacing are yours to get right. Creator will happily let you put Launch Site on a cliff edge.

So, in order:

1. Place it somewhere the topology suits. Look at the topology layer under it, not just the shape of the ground. Painting shows you the layer.
2. Apply its masks. With it selected, the Prefab Modifiers section gives you one button per mask the monument actually carries: Apply Height Mask, Apply Splat Mask, Apply Alpha Mask, Apply Biome Mask, Apply Topology Mask. This is the game’s own data doing the game’s own seating.
3. Keep your own spacing. Two Tier 3 monuments next to each other is a map nobody wants to play, and nothing will stop you making one.
4. Walk in through every entrance in game. A door that opens into dirt, or a step you cannot climb, is invisible from an editor camera and obvious in 10 seconds in game. That is step 18 for a reason.

The alternative to all of this is to let the generator do it: run the Monuments group in TOOLS > Procedural Generation… and move only what you want moved. Every monument it places has passed the whole chain.

Choosing which monuments generate

The generator places every monument family Rust places. To leave some out, use Creator Mode in TOOLS > Procedural Generation…: its MONUMENTS section lists every monument your Rust content carries, grouped by family, each with a checkbox.

• Checked means eligible, not guaranteed. The chain above still decides whether a checked monument lands and where. Checking a monument cannot put it on a map too small for its family, in a biome it does not belong to, or past its family’s own count.
• Unchecked means never placed. The family draws from the monuments that are left, every other family is untouched, and a family with nothing left places nothing. It works the way a Rust server’s own blacklist of that one prefab does.
• To put a monument on a particular island, pin it in the ISLANDS AND ROADS section, when your land is more than one island. A pin moves one of the family’s own count onto the island you name; it never adds a monument the map would not otherwise have.

Standard Mode has no monument list, because a vanilla generation has none: the panel’s Blacklist and Whitelist, which match text fragments of prefab paths the way a Rust server’s own settings do, are the Standard way to keep monuments off. Both are on Procedural generation.

Size, and biomes

Small maps do not just have fewer monuments, they cannot have some at all. Launch Site and the Excavator are the only two monuments in the game with a personal size gate, both at 3500, and everything else is limited indirectly: whole passes skip below their own thresholds, each pass gets fewer attempts on a smaller map, and the same-kind spacing rules a second copy out. The thresholds are on How Rust builds a map.

Biome-locked monuments only exist where their biome does. Arctic Research Base needs arctic, the abandoned military base needs desert. If your map has no arctic, no amount of generating will produce the arctic base, and painting the biome in afterwards does not move a monument that was never placed.

Monument positions move between Rust builds, on the same seed

Between two Rust builds in August 2026, 30 of 38 single-instance monuments landed somewhere else on the same seed. Generation is deterministic in its inputs, not across versions, so a seed you noted down is a seed plus a build.

If you want a specific generated layout to stay put, save the map. A saved .map is a finished world and does not regenerate. See The map file and the sidecar.