Although there is an official API, your photos and videos pulled via the API will have most of their metadata stripped, including GPS location tags.
The best way is via Google Takeout.
If you have a large library, your archive may fail to be generated by Google: you may have to resort to creating several large albums, and restricting your Google Takeout to one album, and creating several Takeouts.
You can only create 3 Takeouts at any given time.
Yes, it's a pain. I'm sure they know.
Know that "high quality" photos and videos frequently have garbled tags, as well. If you've kept backups of your original photos and videos, they'll be much better than what you'll get from Takeout.
(Source: me doing research to support reading Google Takeout metadata sidecars that are then imported by PhotoStructure).
The best way is via Google Takeout.
If you have a large library, your archive may fail to be generated by Google: you may have to resort to creating several large albums, and restricting your Google Takeout to one album, and creating several Takeouts.
You can only create 3 Takeouts at any given time.
Yes, it's a pain. I'm sure they know.
Know that "high quality" photos and videos frequently have garbled tags, as well. If you've kept backups of your original photos and videos, they'll be much better than what you'll get from Takeout.
(Source: me doing research to support reading Google Takeout metadata sidecars that are then imported by PhotoStructure).