Wikipedia

More detailed information can be found on https://wiki-insights.epfl.ch and an interactive demo at https://wiki-insights.epfl.ch/activity-graphs/

You can download a dump of the english wikipedia graph, which you can directly import into a neo4j instance

The dump can be imported using the following command
neo4j-admin load --from=wikipedia_nrc.dump --database=wikipedia.db

The code used to process wikipedia sql dumps, along with instructions, is located on github