European Union Open Data Portal
Everything you can think of in terms of European data is virtually collected in a single portal: the European Open Data portal. How much difference there is between different countries when it comes to height: check. All the documents the European Commission ever established: check. The European population per sexe and age category: check. Even the number of European 18-year olds that are still in school or in training can be found online.
So whether your goal is to be a know-it-all in the pub on Friday nights, or you need data to back up your presentation/essay, it’s always useful to have so many data in one collection and in one spot. The datasets are publicly accessible so you can extract data from them whenever you like.
Photo by: Philippe Put https://www.flickr.com/photos/34547181@N00/