fsn1 or nbg1-dc3
To obtain list of locations, you can use following curl command:
curl -H "Authorization: Bearer $API_TOKEN" https://api.hetzner.cloud/v1/locations
API documentation
To obtain list of datacenters, you can use following curl command:
curl -H "Authorization: Bearer $API_TOKEN" https://api.hetzner.cloud/v1/datacenters
API documentation