# Ground is not flat where it should be

**URL:** <https://community.cesium.com/t/ground-is-not-flat-where-it-should-be/43434>\
**Category:** Cesium for Unreal\
**Created:** [September 23, 2025, 3:47pm UTC](https://community.cesium.com/t/ground-is-not-flat-where-it-should-be/43434 "2025-09-23T15:47:14Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![kuntal\_750](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/kuntal_750/32/28173_2.png) [@kuntal\_750](https://community.cesium.com/u/kuntal_750)\
**Post date:** [September 23, 2025, 3:47pm UTC](https://community.cesium.com/t/ground-is-not-flat-where-it-should-be/43434/1 "2025-09-23T15:47:14Z")

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Hello everyone, I’m new to Cesium and have been using it to create aerial footage for some time. However, I’ve noticed that whenever I try to get closer to the ground, the surface appears wavy. For example, the runway (see attached screenshots) should be flat, but it isn’t. The airport coordinates are: 22.65561349424696, 88.44573379235878.

Could anyone please let me know how to fix this issue? Thanks in advance!

 ![Screenshot 2025-09-23 153851](https://global.discourse-cdn.com/cesium/original/3X/d/8/d8619d61ce467e25361a1d68a187aeafe7bce60f.jpeg)

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**Author:** ![janine](https://sea2.discourse-cdn.com/cesium/user_avatar/community.cesium.com/janine/32/5135_2.png) [@janine](https://community.cesium.com/u/janine)\
**Post date:** [September 26, 2025, 7:57pm UTC](https://community.cesium.com/t/ground-is-not-flat-where-it-should-be/43434/2 "2025-09-26T19:57:17Z")

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Hi @kuntal_750, welcome to the community!

It’s possible that some regions on Cesium World Terrain are outdated due to the older height data. There are some suggestions on this other forum thread here:

> [@How to edit terrains, like elevating, flattening, adding roads in Unreal?](https://community.cesium.com/t/how-to-edit-terrains-like-elevating-flattening-adding-roads-in-unreal/39759/2):
>
> Hi @Onyx_Lee, Which tileset are you using? There’s no way to import a 3D Tiles tileset as a landscape and sculp it, unfortunately. But if you’re using Cesium World Terrain, and you have better heightmap data for your area, you can upload that to Cesium ion and create a local overlay on top of Cesium World Terrain. Then you can access the combination from Cesium for Unreal as a single tileset. Another possibility - once again assuming you’re using Cesium World Terrain - is to export your area …

You could also try using the **From Ellipsoid** option on `Cesium3DTileset` to build on a smooth ellipsoidal surface. However, this does smooth out the entire Earth, so it will look less realistic from afar.