Hello Adrian,
We do not have the documentation available to create Location Extensions through Ads API. You may follow the same steps as in
AdWords API to implement the Location Extensions in Ads API. The
FeedService will create the Location Feed and then use the
CustomerFeedService to associate the customer to the Feed created. Could you please give this a try and let us know if you have any issues?
Thanks,
Bharani, Google Ads API Team

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