Some of these places lie within the English ceremonial county of Berkshire in the UK, but others don't. Click on the Berkshire places without clicking on anything else!
Start by naming any country that France borders. Then name any country that borders any of those countries. Then keep going until there are no more countries left to name.
Perhaps it should be made clear that this is the "ceremonial" county of Berkshire given its current boundaries. Prior to 1974 Abingdon was part of Berkshire and was actually the County Town, the County Hall and old gaol are still standing there today.
I made a series of these myself, a while ago - here is the link to them:
https://www.jetpunk.com/series/1374763/english-counties-sudden-death