Fiona

Your issue is that you're using the default (old) binding to GDAL, based on Fiona [0]. You need to use pyogrio [1], its vectorized counterpart, instead. Make sure you use `engine="pyogrio"` when calling `to_file` [2]. Fiona does a loop in Python, while pyogrio is exclusively compiled. So pyogrio is usually about 10-15x faster than fiona. Soon, in pyogrio version 0.8, it will be another ~2-4x faster than pyogrio is now [3]. [0]: https://github.com/Toblerity/Fiona [1]: https://github.com/geopandas/pyogrio [2]: https://geopandas.org/en/stable/docs/reference/api/geopandas... [3]: https://github.com/geopandas/pyogrio/pull/346