> For the complete documentation index, see [llms.txt](https://docs.world-creator.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.world-creator.com/walkthrough/run-simulations/add-sand.md). # Add Sand To further polish our terrain, we now move on to [Simulation Layers](/reference/terrain/simulation-layers.md). Simulation Layers provide high quality physical simulations such as [Sand](/reference/terrain/simulation-layers/sand.md), [Fluid](/reference/terrain/simulation-layers/fluid.md), [Snow ](/reference/terrain/simulation-layers/snow.md)or [Debris ](/reference/terrain/simulation-layers/debris.md)that work with simulated material on top of the filter stack. Since we want to create a desert canyon, we will use the sand simulation first. After adding the Sand layer, click **Edit** and mask out the area where the sand will spawn. By default, each simulation layer comes with its own paintable mask.

To texture our sand we create a new material, give it a sand like colour and drag the sand simulation layer into its distribution stack. This creates a [simulation layer distribution](/reference/terrain/distributions/layer/simulation.md) that references the sand layer.

To further enhance the scene we then add a second sand simulation using a darker material. This time we do not mask it, instead we reduce the **Spawn Amount,** which then results in a nice global fade effect.

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