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# ST_MaximumInscribedCircle
Introduction: Finds the largest circle that is contained within a (multi)polygon, or which does not overlap any lines and points. Returns a row with fields:
![ST_MaximumInscribedCircle](../../../image/ST_MaximumInscribedCircle/ST_MaximumInscribedCircle.svg "ST_MaximumInscribedCircle")
- `center` - center point of the circle
- `nearest` - nearest point from the center of the circle
- `radius` - radius of the circle
For polygonal geometries, the function inscribes the circle within the boundary rings, treating internal rings as additional constraints. When processing linear and point inputs, the algorithm inscribes the circle within the convex hull of the input, utilizing the input lines and points as additional boundary constraints.
Format: `ST_MaximumInscribedCircle(geometry: Geometry)`
Return type: `Struct<center: Geometry, nearest: Geometry, radius: Double>`
Since: `v1.6.1`
SQL Example:
```sql
SELECT inscribedCircle.* FROM (
SELECT ST_MaximumIncribedCircle(ST_GeomFromWKT('POLYGON ((62.11 19.68, 60.79 17.20, 61.30 15.96, 62.11 16.08, 65.93 16.95, 66.20 20.61, 63.08 21.43, 64.48 18.70, 62.11 19.68))')) AS inscribedCircle
)
```
Output:
```
+---------------------------------------------+-------------------------------------------+------------------+
|center |nearest |radius |
+---------------------------------------------+-------------------------------------------+------------------+
|POINT (62.794975585937514 17.774780273437496)|POINT (63.36773534817729 19.15992378007859)|1.4988916836219184|
+---------------------------------------------+-------------------------------------------+------------------+
```