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# maximumRegionMonitoringDistance

The largest boundary distance that can be assigned to a region.

```
var maximumRegionMonitoringDistance: CLLocationDistance { get }
```

## Discussion

This property defines the largest boundary distance allowed from a region’s center point. Attempting to monitor a region with a distance larger than this value causes the location manager to send a [`CLError.Code.regionMonitoringFailure`](/documentation/CoreLocation/CLError-swift.struct/Code/regionMonitoringFailure) error to the delegate.

If region monitoring is unavailable or not supported, the value in this property is `-1`.

---

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