Zenodo
Zenodo was created by CERN, the European physics laboratory, to give researchers anywhere a free place to publish and preserve their work. It accepts almost any file type and any subject, from small spreadsheets to large datasets, alongside the code and papers that go with them.
Each deposit receives a DOI (Digital Object Identifier), a stable link that keeps working even as the underlying storage changes, so citations do not rot. You can browse and download openly, search by topic or community, and pull records through the Zenodo API for bulk access.
Licences are chosen by whoever uploads each record, so check the terms per item. For RAG, Zenodo is a good source of curated research datasets and the cleaned, documented versions of corpora that authors often publish here, including standardised builds of well-known collections.
Related sources
AWS Data Exchange
A marketplace for finding, subscribing to, and using third-party data inside the AWS cloud. It carries both free open datasets and paid commercial data products, so you can pull licensed data straight into your AWS workflows without setting up separate transfers.
AWS Open Data Registry
A registry of high-value datasets hosted on AWS and made publicly available, covering genomics, geospatial data, climate, satellite imagery, and more. Over 300 PB of data in total, free to access: you pay only for the compute you use to process it.
Datahub.io
A platform for publishing and finding open data packages: datasets bundled with consistent metadata in standardised formats. It hosts curated collections of widely used reference data, from country codes to exchange rates, ready to drop into a pipeline.
Google Dataset Search
A search engine for datasets that indexes millions of them from thousands of repositories worldwide. It does not host data itself: it points you to wherever each dataset lives, which makes it a fast first stop when you are hunting for a source on a specific topic.