> ## Documentation Index
> Fetch the complete documentation index at: https://docs.notifense.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Geofences

Geofences can be used for alert rule filtering. and, if using the [event generation service](./telemetry), for generating geofence events from telemetry data.

## Creating geofences

Geofences can be created using the `POST /v1/accounts/{accountId}/geofences` endpoint. To create a geofence for a specific asset group, use the `POST /v1/accounts/{accountId}/assetGroups/{assetGroupId}/geofences` endpoint.

A geofence can be created by specifying the midpoint of a circle and its radius, or by specifying the points around the outside a polygon. The polygon must be counter-clockwise and closed (i.e. the first and last points of the line must be the same).